Entry for the Phic Phight 2019. The prompt by Illusn was: Jack Fenton thought that all ghosts were evil, until he met a certain ghost dog.

If there was one thing that Jack had been taught by his parents, it was that ghosts were evil. Every single specter, every single ectoplasmic being, they were all evil beyond salvation. Malevolent or sometimes just too thoughtless to know better, every single ghost was dangerous and harmful. There were no exceptions to this.

Dutifully, every member of the family told the rest. Parents told their children, grandparents told their grandchildren, and even aunts and uncles told their nephews and nieces. No one in the Fenton family went untold – and it was told many, many times over.

Even if life seemed intent on proving this old family knowledge wrong, Jack knew better. Even if Phantom continued to brainwash the town and the other citizens into believing him to be a protector, Jack knew better.

The small dog sitting in front of him barked. Its tail, a green flare not even connected to its body, was wagging so quickly that Jack couldn't even track it properly. Its tongue lolled out of its mouth, which was stretched wide in a doggy smile.

It was an animalistic ghost. It was too feral to do anything but act on its impulses. It should be acting on its ghostly instincts.

It should be attacking him.

It wasn't.

It was just… behaving like a dog. Like a regular living dog.

Jack crouched, slowly to avoid spooking the ghostly dog. But it remained seated, wagging up a storm.

Frowning, Jack extended a gloved hand towards the ghost. Still, it didn't move. Not even when his hand landed on the ghost's head.

Why wasn't it attacking? Especially now that he was touching it? Shouldn't the ghost's protective instincts kick in now? Not that Jack wanted to be mauled by a dog far smaller than him, but… it was weird. It went against all his knowledge, all his expectations.

Slowly, haltingly, Jack started moving his hand over the dog's head. Ruffling its fur. The dog, in turn, squinted its eyes closed in pleasure. Its tongue lolled out even further.

Jack moved his hand, tickling the dog under its chin. The dog started scratching along with its hind leg.

It really was acting just like a regular dog. But its fur was green, and its eyes, before it had closed them, had been empty and red.

It was a mystery. And Jack… Well, Jack loved mysteries. Especially ghostly mysteries. How exciting! And this ghost, for whatever reason, was fine with his touching. Maybe he could research it without getting attacked!

Grinning to himself, Jack scooped up the small green canine. It fit into his arms easily, and Jack carried it pressed against his chest, leaving his right arm free so he could drive the GAV back home. And sure, maybe driving with one hand was dangerous, but his driving didn't seem any worse than usual. He didn't hear more honking, anyway.

"Mads?" he called, throwing open the door to FentonWorks. He made sure to raise his volume enough so she could hear him in the lab, but no answer came.

He moved closer to the lab, still carrying the ghost in his arms. "Mads?" he tried again. Still no answer.

Once he had thumped down the stairs, Jack realized that Maddie wasn't there at all. Frowning, he moved over to one of the nearby tables, where he found… Ah, a note!

Oh. Maddie was out getting groceries. Hopefully she would remember to bring him some fudge. They could celebrate the new discoveries he was about to make thanks to this ghost dog!

Surprisingly gently, he put down the green canine on one of the examination tables. The dog, still panting and wagging its tail, sat down immediately.

Jack ran a hand over the dog, starting at its forehead and following the line of its spine. Then he frowned and repeated the motion, stopping at the neck. He dug his fingers into the plush fur, pushing it aside to reveal a spiked black collar.

He followed the line of the collar to the front, where a small round tag hung off it. Ducking down and hooking a finger underneath the tag to raise it up as well, Jack inspected it. The tag was made out of metal and primarily gray, but with a large blue A on it. Surrounding the A where two crossing rings, with four small blue dots on them.

Was this… the Axion Labs logo? Why would a ghost have such a logo on it, especially an animal like this one?

Unless… Unless it came from Axion Labs? Was it a guard dog before it died?

Jack shook off the macabre thoughts. It would do him no good to dwell on such things. He had to focus on the more important questions. Like why the ghost was acting like a regular dog instead of, well, a ghost.

An hour later, Jack still hadn't figured out anything. There was nothing about this ghost that separated it from normal ghosts. The readings he was getting from its core were, if anything, higher than normal, rather than lower like he expected. The ghost was powerful for its small posture, but didn't seem inclined to act on it.

It even let Jack handle it without trouble. He hadn't done anything inhumane – insisted to himself that he didn't want to risk damaging a valuable specimen, not that he had grown fond of the ghost – but still. Most ghosts wouldn't have let a human touch them, never mind the in-depth tests that Jack had run on it. He had even taken a saliva sample from the ghost!

Turns out that it produced a diluted form of ectoplasm! From its mouth! To mimic a regular bodily function it had no right to express! How incredible! Even the act of panting, which was how Jack had thought to check for saliva in the first place, was something that the ghost shouldn't be doing. After all, panting was a form of breathing – and ghosts didn't breathe.

Well, Phantom did sometimes, but it was fond of pretending to be more human than it really was. Part of its nefarious plan to trick the city, surely. After all, if the people of Amity Park saw it as human, ghost hunters like Jack and his wife were harder pressed to stop it. Random civilians would reprimand them for hurting something so human, completely ignoring that it wasn't.

He eyed the ghost dog speculatively. It was still sitting right where he had left it, big red eyes focused on him. It had stopped panting, and its wagging tail had slowed somewhat. It was better behaved than most living dogs, Jack thought. Maybe… Maybe he could train it?

Although it was a little small. Even if the measurements suggested that it was a moderately powerful ghost, stronger than most animalistic ghosts and the weaker humanoids, it didn't seem that way. Did it have some sort of hidden ability?

A door slammed upstairs, snapping Jack out of his thoughts.

"Jack, honey, are you home yet?" his wife called. Jack brightened up immediately. He couldn't wait to show Maddie the bizarre canine he had found.

"I'm in the lab!" he shouted back, unnecessarily loud. The green dog, which had looked towards the stairs when it heard Maddie, focused back on him. Its blinked at him for a moment, the empty red eyes unreadable… and then it started wagging its tail again.

"I bought you some fudge," Maddie said as she came down the stairs, "But you can't have it until after dinner, okay honey? Did you catch any—"

She fell silent when she saw the ghost sitting on the table in front of him. The dog had set its red gaze on her as well.

"Well," Jack started saying. Before he could continue, however, the dog growled.

Then it barked, low and echoing. It lowered its chest to the table, raising the hind end – its tail completely still and flaring straight up.

"Jack-" The single word sounded reprimanding, but Maddie didn't get to finish her sentence either.

The ghostly canine leapt off the table, looking like it was attempting to bowl Maddie over. It didn't look particularly threatening, since the dog was barely tall enough to come up to her knees.

Except that it somehow grew in size. Mid-air.

By the time it hit Maddie, the ghostly canine was so large that Maddie barely reached its chest. And it was coming at her with a quite frankly terrifying speed.

Suddenly Jack understood why the ghost had measured so highly on the strength scale. But why had it suddenly turned aggressive?

He ran over to the canine, pushing against the furry side. "Stop!" he yelled, more for the idea than out of the expectation that the ghost would listen.

But it halted, lips pulled back and teeth bared. Its head was tilted towards him slightly, as if it were listening to him. Would it listen to commands still?

"Get off her!" he commanded, sternly.

The ghost hesitated for a moment. Then, unbearably slowly, it lifted its enormous paws off of Maddie. It took a few steps away from the two humans.

"Sit," Jack demanded. And, with a thud, the enormous ghostly canine sat down.

Maddie pushed herself partly upright, leaning on her hands. "Jack," she said, stressing the one word.

But Jack ignored her, moving closer to the canine ghost. He didn't understand. The ghost had been perfectly docile the whole time! Why did it lash out now, of all times? Had Maddie startled it somehow?

Would it still be possible to train it?

Cautiously, he reached out towards the dog with a single hand. It was dwarfed by the ghost now, barely the size of its eye.

It didn't move. Not even when Jack laid his hand on the ghost's muzzle. He bit his lip, then scratched the dog under its chin.

For a few moments, nothing happened. Then the dog's tongue lolled out of its mouth again as its tail started thumping against the floor. Moments later it started scratching with its hind leg too.

Then with a pop, it returned to its smaller size.

Maddie, having gotten off of the floor while Jack was distracted, stepped next to him. The dog stiffened momentarily, but relaxed again when Jack patted it.

"Jack," she repeated once more. Then, because she wasn't interrupted by a canine cannonball this time, she continued, "We can't keep it."

"But Mads," Jack grabbed the dog and held it up to her face, "It's totally obedient. It would make such a great hunting dog!"

She stared at him, unimpressed. "Jack. It's a ghost."

"Exactly! It can chase after the other ghosts, into places where we can't get as easily!"

An even less impressed glare. "It's a ghost. It's a violent malevolent being. You can't train it, and you definitely can't keep it." Then she brightened up a little. "Except for experimenting, of course."

He gasped, offended, and pulled the ghost against his chest. "I've already done experiments on it! It was very well-behaved! And," he ducked down and put the dog back onto the floor, "it's obviously trained already."

"It also attacked me the moment it saw me," Maddie reminded him, crossing her arms.

Well, that he couldn't deny. "Maybe… Maybe you startled it?" He offered her a sheepish grin. "Or maybe it was already a little put-off from being in the lab?"

Maddie's sharp gaze lingered for a moment longer. Then she sighed, her shoulders slumping down. "Why don't we continue this conversation upstairs, then?"

Jack nodded his approval, moving to the stairs. The ghost dog hesitated for a moment, then trailed after him. Maddie lingered for a little longer, then followed the other two up the stairs.

"I don't understand why you took it home in the first place," Maddie said as she entered the living room. "Besides for studying, of course."

"Well… That was kind of what I was doing," Jack confessed, grinning a little. "I ran into it while hunting, and it didn't behave like normal ghosts. So I took it here to study it."

He grabbed the small dog off of the floor and put it onto his lap, patting it with one massive hand. "I noticed that it behaved like a plain old dog, instead of as a ghost. But none of its results came out any different!"

"So then there is no guarantee that it is any different." Maddie crossed her arms, sitting down in an armchair rather than next to Jack on the couch. He would feel offended, but he was pretty sure she was avoiding the ghost, not him. "Or that it can be trained to behave differently."

"Well, no-" Jack started saying, but he broke off when the dog leapt off of his lap and onto the floor. It stood still for a long moment.

Then its ears perked up, as if it had heard something outside. Its tail started wagging up a storm again.

"Mads," Jack interrupted the incoming rant from his wife, "Look at the dog."

She snapped her mouth shut and turned to look. The green canine now stood crouched, its upper body lowered to the ground. Its tail was still moving wildly, its tongue lolling out of its mouth. It barked once, sharp and… excited?

"What is it responding to?" she asked, or started to ask. But the door opened and the dog shot off like a bullet from a gun.

Jack, and based on her reaction Maddie as well, immediately thought back to the lab earlier. They got out of their seats, ready to pull the dog off of their child-

But they stopped when they heard laughter, of all things.

"C-Cujo?" Danny's voice rang out, in-between chuckles. "What're you doing here, boy?"

Jack moved in closer, and could now see that the dog had remained small. It had tackled Danny flat onto his back, and stood on his chest, wagging up a storm. It was also liberally covering Danny's face with ectoplasmic drool. Jack was glad that he had researched that, so he knew that it was safe.

"Danny-boy!" he boomed instead. "Do you know that little rascal?"

Danny shot upright, eyes big as he looked at Jack, then Maddie, and then finally at the small green dog which he now held in his hands. "I, uh…"

Maddie sighed, heavy and weary. "Like father like son, I suppose." Then she shook her head and set a harsh glare on their son. "But you should know better than to associate with ghosts, young man."

Danny grinned sheepishly, setting down the dog on the floor next to him. As he stood up, he said, "Cujo didn't exactly give me a choice. He keeps coming to me. At least if I keep an eye on him, I can make sure that he doesn't cause any trouble."

Her gaze lingered for a moment longer, then the tension leaked from her shoulders again. "I guess I can't punish you for it if your father did the same."

Danny's face brightened, and he scooped the dog off of the floor again. What had he called the ghost? Cujo? "Thanks mom." Then he seemed to process the rest of the sentence, as he frowned. "Wait, what do you mean 'dad did the same'? How did Cujo even get here?"

"Ah." Jack scratched his cheek, uneasy now that both Danny and Maddie were looked at him, gazes expectant. "I, uh. Ran into him while ghost hunting."

"And you didn't shoot him/it?" Danny and Maddie questioned simultaneously. Then they shot each other a look, before turning back to him again.

"Yes, well. No, I mean." Jack was feeling increasingly nervous under the watchful eyes of his son and his wife. "I noticed that its behavior was off before I got a chance to. And then I was curious as to why it was so different, so I took it back to the lab."

Danny stiffened, eyes flicking down to the dog in his hands. "You studied him?" he asked, horrified.

Jack flapped a dismissive hand. "Nothing invasive. And it didn't mind, I don't think. It certainly didn't try to attack until your mom came in."

"Oh." Danny held out the dog to glare at it. "Cujo," he said with a reprimanding tone, "No attacking humans! I keep telling you this."

The dog continued to wag his tail, yipping in answer. Danny sighed, pulling the dog closer to his chest again.

"Does it ever listen?" Maddie wondered, looking intrigued at the display. "Or can it not be trained?"

Shifting the dog into one arm, Danny used his other to make a so-so motion. "He usually listens, although sometimes it takes some repeating before he remembers. But he always listens if you tell him to stop."

"Like in the lab, then." Maddie turned to look at Jack, calculating. "And you say that it can be trained?"

"Uh, yeah." Danny shifted from one foot to another, uncomfortable now that he was in the spotlight again. "Although he is already trained in some of the basics. I'm pretty sure that he was a guard dog before he died, or trained to be one, at least."

"That's right!" Jack perked up at the mention, remember the tag on the dog's collar. "I saw the tag. Axion Labs, right?"

But Maddie shook her head dismissively. "Why would one of their guard dogs die, let alone become a ghost?"

"Uh, because Axion put down all their dogs when they got a new security system?" Danny frowned, the corners of his mouth pulling down. "I dunno why Cujo became a ghost, specifically, but I know that that was a thing." He didn't explain how he knew.

Jack would've questioned him about it, but he got distracted by the proof that the ectoplasmic canine could be trained. "See, Mads," he boomed, smiling widely, "Just like I said! It could make a fantastic ghost-hunting hound!"

"Or a pet," Danny grumbled under his breath, cradling the ghost to his chest.

"Nonsense." Jack scooped the dog from Danny's arms, holding out towards Maddie. "Besides, you've already seen its potential. I can't wait to see Phantom's expression when this ghost catches it!"

"Actually," Danny interrupted, stepped closer as if thinking about grabbing the dog back. "I don't think that that will be happening. He likes Phantom."

Maddie's eyes snapped from the ghostly canine in front of her to Danny. The boy in question flinched back a step. "How would you know that?"

"Cujo keeps following me, and Phantom hunts down every ghost in the city." Danny thew up his hands in exasperation. "Of course I've run into him!"

She eyed him for a moment longer. Jack slowly put down the dog, careful not to draw her attention – or her ire. "Fine. But you're wearing a Specter Deflector to make sure Phantom stays away from you."

"What?" Danny's eyed widened, and he took another step back. "No! Phantom is harmless, and he never tried anything to hurt me or Cujo! Quite the opposite – he's the reason why Cujo wasn't constantly following me around!"

"But you should know better than to associate with ghosts," Maddie insisted, crossing her arms. "And they're clearly influencing you already – you of all people should know that Phantom isn't a he but an it."

Danny scoffed, rolling his eyes. He didn't answer.

After that, the silence turned awkward. It lingered for what felt like an eternity.

And then the door opened again.

The ghost dog shot off of the floor again, launching itself at whoever was in the door opening. Jazz, probably, since no one but their family walked straight in. Well, Sam and Tucker did sometimes, but usually they were with Danny when they did that.

Jazz screeched, but managed to catch the dog in her arms before she went down. Jack involuntarily let out an impressed whistle.

"Good catch," Danny complimented, blinking away his surprise. His sister just grumbled out an incomprehensible answer as her face was slathered in ectoplasmic drool.

"No worries, Jazzy-pants," Jack comforted as he moved to pick the dog out of her arms. "It's not dangerous."

Jazz shot Danny a glare, then turned to her dad. "The dog or the drool?"

"Both," Danny said, as Maddie simultaneously answered, "Neither." They shot each other a glance again, Danny's expression sheepish while Maddie looked tired. Or angry. Maybe both.

"The drool," Jack affirmed, taking the ghost into his own arms. "And arguably the dog, too. We were still talking about getting it trained to hunt ghosts."

"Really?" Jazz quirked an eyebrow, unsure. "You want to train a ghost to hunt other ghosts? But when Phantom does it, it's a sign of dishonesty and evil plans?"

"Well, yeah." He raised the dog up, as if he was showing it off. "Because this is gonna be a ghost that is following the instructions of its human masters. Phantom is a rogue spirit."

"What if he wasn't?" Danny licked his lips, nervous as the other three turned their attention to him. "What if… What if a human was instructing Phantom to protect Amity from other ghosts?"

Maddie snorted. "Then they would be borrowing trouble. Sooner or later, Phantom will turn on them – and the town. You can't control a ghost."

Aggravated, Danny waved a hand at Jack and the ghostly canine in his arms. Maddie rolled her eyes. "Yes, even that one. As I've been saying, Jack, we can't keep it."

"Aww." He lowered the ghost again, holding it at chest level. "But imagine how much it could help with ghost hunting!"

"No," Maddie repeated, firmly. Her eyes were steely, sharp and cutting. "Either it goes into the Ghost Zone, or I'm taking it down to the lab for examination."

Danny gasped, and Jazz winced. "Fine," Jack sighed, cradling it closer to his chest.

Maddie's eyes lingered on the spectral canine, committing it to memory. There was no doubt in Jack's mind that she would recognize it, if it ever returned. And, if Danny had been telling the truth, it likely would.

He walked back into the lab, his footsteps echoing in the silent room. More footsteps, quieter, followed him. He turned, expecting to see Maddie. Instead he saw his son, who shrugged under his father's watchful eye.

"Just wanted to make sure you actually let him go," the boy confessed. Then, after a moment, "And to make sure he doesn't immediately come back. I think he digs through the Portal doors, somehow."

"Ah." That explained it. Danny was worried about the canine. He was always a bit of a hero. Protector of those who couldn't do it themselves. It made sense that he stood up for the ghost.

It made sense that he defended Phantom. He saw himself in the spirit.

And maybe… Maybe his son had a point.

Jack looked at the small ghost in his hand. It panted at him, wagging its flame-like tail. If this animalistic ghost defied its nature, why couldn't a more humanoid one?

Danny opened the Portal as Jack stood in front of it. Once the doors were fully opened, Jack carefully took the dog towards the swirling green mass.

"Goodbye Cujo," he said, as the ghost was drawn back into its home dimension.

He had a lot to think about.

Cujo is the Best Boy and you can't tell me otherwise. Also an exercise in "Jack Fenton is too hyper for me" and "how often can you pick up a dog in one fic?" (the answer is: very often).

As always, feedback and critiques are very welcome! Also please tell me if "[...] more for the idea than [...]" is actually a thing in English or not. Because I have the feeling that it's not and that I just stole it from Dutch but brains are stupid and language is fake.