Return of the Scathing Moon

By Fai Gensou

Summary: What would have happened if Isshin regained his powers the night Ichigo became a Shinigami? A Bleach rewrite with Isshin pounding all he knows into his son, with Rukia and Urahara's help of course. Just what kind of difference will this lead to?

Disclaimer: Would I be working in a department store if I owned any of this?

Chapter 1

Isshin hadn't been lying per se about not being able to see ghosts, considering all he saw were fuzzy bits. He saw the figure standing next to his son, if only as a black blurry mass, and hear it too, just at the edge of his hearing.

As he returned downstairs to be the crazy idiot father his children saw him as, Isshin pondered on how much Ichigo's reiatsu had increased within the last couple months. It had always been the strongest out of his three children, but once he hit puberty and entered high school, it was like someone had it hit fast forward on its growth. That wasn't unusual, according to Urahara and Ryuken when he asked (bugged in Ryuken's case) about it, since dramatic life changes can increase reiatsu in those who already possess it, puberty being the biggest and most common reason. Ryuken had reported it happening in his own son, who in a quirk of fate was in Ichigo's class. Karin and Yuzu's own reiatsu would be increasing soon, with girls entering puberty earlier than boys.

Crying to Yuzu over Ichigo's latest hit, Isshin wondered if he needed to bug Tessai about improving the shielding on his house, since Ichigo's recent increase in reiatsu had eroded the current ones enough for ghosts to enter. It would only be a matter of time before-

His back exploded in pain and he crashed into the wall, blacking out for a moment. As the world came back into focus, he heard, like a bad radio transmission, a voice. "Sto…human's stre…break the kido! If you…your soul…!" With the blast of reiatsu that washed over his dulled-but-strengthening senses, Ichigo came barreling down the stairs, the shinigami close at his heels, running to get Yuzu out of the Hollow's grasp.

Yuzu safe, Isshin wondered just where Urahara was, and if he was nearby, why he hadn't intervened yet. As unusual as the man was, he knew he wasn't one to abandon a friend. Unless this was sort of test of Ichigo, in which cause Isshin was gonna beat his ass.

"Fool…did you think it would be over if you gave him your soul? Then you are a fool!" Isshin raised his head to see the now-slightly-blurry figure of the shinigami lying wounded on the ground, having stopped his son from sacrificing himself to the Hollow.

"I'm sorry… I just wanted to…"

"I fear…I cannot console you…I am too badly injured to fight it…it is a matter of time…until we all become its food." Isshin could practically hear Ichigo beating himself up over the fact his family was in danger because of him. He saw the shinigami push herself into a sitting position. "Do you wish to save your family?"

Dumb question to be posing to Ichigo, Isshin mentally commented.

"Just tell me how! I'll do anything! Tell me!"

"There's a way…I should say…there's only one way…" she raised her sword. "You must become a shinigami!'

Ichigo was dumbfounded. "What…what are you talking about? I can't be a—"

"You can!" She argued. "Place the zanpakutou over your heart, and I will infuse you with half of my reiatsu. You will temporarily have the powers of a shinigami, giving you a chance to fight the Hollow."

Ichigo was a little doubtful, but Isshin knew there was only one choice Ichigo would make. "Are you sure you can do something like that?" Isshin was a little curious too, since most Shinigami wouldn't even think of this option, and not many below taicho or fukutaicho had the power to even attempt it.

"I don't know. Perhaps because your soul is so powerful, but…the chance of success is low. If we fail, we die! But there is no other way! Nor the time to ponder it!"

"Ichi-nii…don't come…danger…" Yuzu murmured. Ichigo's resolve crystallized into diamond.

"Gimme your sword, shinigami! We'll try your plan." He walked over to stand in front of the shinigami.

"Not "Shinigami". Kuchiki Rukia." Well, that answers how she would know of an unusual option.

"I'm Kurosaki Ichigo. Let's pray this won't be our last meeting." Unnoticed by the two, Isshin watched a zanpakutou be run through his son's heart, and a blast of reiatsu wash over the area.

Rukia had intended to only give Ichigo half of her power. But Ichigo was half-Quincy, and even untrained, it was still part of his nature to absorb reiatsu. Ichigo also leaked power like a sieve. Because of these two factors, enough power-shinigami power-left Ichigo to be picked up by Isshin, and all of Rukia's powers to be taken. Isshin's vision achieved a clearness he hadn't seen in two decades. Not since he gave up his power for a girl who would become his wife.

Despite the manner in which it occurred, Isshin was filled with pride to see his son in the shihakushou. He'd have to talk to Urahara about acquiring an asauchi for Ichigo, seeing as his current sword was nothing more than a sword-shaped mass of reiatsu. He didn't doubt Urahara's ability to get one; the man could get anything Soul Society had to offer, despite the criminal offense it was to obtain items from Soul Society for sale in the Living World. Isshin was starting to relax with Ichigo's defeat of the Hollow, when another Hollow appeared, stabbing a claw through Ichigo's stomach.

"Ichigo!" Rukia yelled. Ichigo fell to his knees, clutching his stomach, panting. It wasn't quite the failure Rukia had feared happening, but it was still a failure. Kaien-dono…Nii-sama…

Isshin struggled to move, to do anything, when a familiar presence appeared at his side. "Did you forget about me?"

Isshin chuckled. "I apologize. I hadn't realized my power has recovered enough to call you."

"It hasn't, not really. Enough of the young one's power leaked from your son to give me a chance to come to you. Releasing me will recover your power enough that the rest is only a matter of months for you to return to full strength. I hope you haven't forgotten my name."

"It would take a long time for me to forget your name my friend."

Rukia and Ichigo were waiting for the end, since the Hollow newly arrived on the scene was taking his time deciding who to devour first. He hated orange, but female souls were always so tasty…

"MOERO, ENGETSU!" An overwhelming reiatsu washed over them, as a sword wreathed in ethereal fire split the Hollow cleanly in two.

Ichigo and Rukia could only stare at the back of the figure, one they had seen lying on the floor moments earlier, now dressed in a shinigami's shihakushou. A band of white cloth was tied to his left shoulder, and as the wind blew, the cloth fanned out, revealing the kanji for 'ten' inside a diamond. Rukia's eyes widened, and her breath caught in her throat. Ichigo, however, was more vocal in his shock.

"OYAJI?!"

End of Chapter 1

Note: I'm following the manga version of events, where Isshin is present when the Hollow attacks, and Yuzu is held by the Hollow, not Karin. Isshin's zanpakutou's name and release phrase come from the Bleach Wikipedia.