"When I see Cyborg next," Raven grumbled, "I am going to murder him."

At least, that's what she tried to say. What came out was something of a "mrphgrph" mumbled around the mechanical cock stuffing her mouth with its warm metal girth. Starfire, meanwhile, was trying to fight off the artificial tentacles that, like with Raven, were binding all her limbs and stuffing her mouth with a metallic cock.

It had all started with a regular night of girl bonding in the Tower, the pair training in Titans Tower's purpose-built room. Things had all gone downhill when Raven, in an unwise word choice, casually said "oh, fuck me" after being knocked down by one of the robotic training dummies.

This was a mistake, for it seemed that Cyborg had programmed some rather unorthodox features in the training room's coding.

All the lights had turned red, and the Tower PA system blared out to the room - and hopefully, Raven and Starfire each thought, not to the entire tower - "EROTIC TRAINING PROTOCOLS ENGAGED. SYSTEM SETTING: ENDURANCE MODE."

With that, several tentacles had appeared out of the floor next to the two girls and efficiently bound them, wrapping tightly around their limbs and lifting them off of the ground, disorienting them. Additional tentacles jammed themselves into their mouths and began to thrust relentlessly.

And this is how we find our heroines, immobilized and mouths stuffed with mechanical dick.

The tentacle-cocks retreated from their mouths, leaving the both of them coughing and spluttering, but able to speak once more. Raven, more used to having foreign objects fuck her mouth, was the first to recover.

"I'm serious," she said, "I am going to murder him."

"What do you think is the purpose of all these contraptions?" Starfire asked. Raven was unsure of whether or not to tell the poor naive girl or let her discover for herself exactly what was going on.

"Cyborg has been playing games," she said with distaste. "He's turned our training room into a goddamn sex dungeon."

"A… sex dungeon?" Starfire asked.

"The machinery in here is going to fuck us," Raven explained. "It said it was on endurance mode, so we're probably in for it, too."

"O-oh," Starfire said, a blush spreading across her face as she began to understand. "Can we not… call for help, or something of that nature?"

"Not with our comms over on that table," Raven responded. "And it seems that these tentacles are equipped with inhibitor tech. I can't use my powers."

"Let me try using my starbolts!" Starfire exclaimed. But when she flexed her wrist to summon a bolt of energy, her powers spectacularly failed to manifest. There was a slight spark, but that quickly faded. Far from enough to break either of them free from their bondage.

It turned out that that much wasn't necessary, at least, as the tentacles unceremoniously dropped them and slithered back into the floor.

"Oh, thank the gods-" Starfire said, but she spoke too soon and her face turned to dismay as the security blast doors dropped, trapping them in the room - and, undoubtedly, deadening any sound or comm signals that tried to escape.

They were well and truly trapped.

Small panels hidden in the walls retracted, and out flew various hovering mechanical devices of unknown purpose - although Raven had her suspicions. Several of the flying devices, round rings of polished metal, secured themselves around the girls' wrists and ankles and locked into place. The rings charged with energy, and they pulled the girls up as the wrist cuffs flew into the air, putting them in much the same position as the tentacles had put them in.

The tentacles returned from the ground, this time sporting wicked-looking pincer claws. They made quick work of slicing through and pulling off Raven's and Starfire's clothing, their customary superhero uniforms. The cuffs then turned them so that they were facing each other with only the barest shreds of clothing around the fringes of their bodies.

Starfire looked at Raven's naked body and began to blush again, despite herself admiring Raven's modest but firm breasts and trimmed but unshaven pubic hairs. Starfire, for her part, was quite beautiful with larger breasts and a fully-shaven pussy. Raven could not help but admire her naked form as well, despite the embarrassing and unasked-for situation.

The two of them nude and facing each other, Starfire was the first to break the silence. "Um," she said, "what do you think comes nex-" She was interrupted by a floating orb the size of a golf ball jamming itself into her open mouth, gagging her.

"Star-" Raven shouted, but an identical ball invaded her open mouth and silenced her as well, the rest of her exclamation coming out as a muffled grunt.

The tentacles, which had been standing by, transformed from their pincer forms and the ends morphed into bulbous knobs at the end, looking much like cock-heads. These tentacles started to rub the tips up and down their bodies, leaking a milky-white substance that Raven, if not Starfire, was all too familiar with.

They were leaking cum all over the girls' bodies.

Raven and Starfire tried to squirm away, but to no avail as the metal cuffs were unrelenting and stayed in the air as if bound in concrete. In fact, the more they fought against them the firmer their restraints seemed to get, as if they were feeding off the kinetic energy of their struggling.

The cum-leaking tentacles seemed to take a special interest in Starfire's ample breasts, two of them pressing the tits together as a third pumped its way in and out of her cleavage, covering her breasts in sticky white seed.

Most of Raven was relieved that she was not receiving such treatment, though a small part of her thought What, are mine not good enough? - though she knew that was an irrational thought. Nevertheless, seeing the tentacle thrust against her friend in a forced boobjob made her skin feel hot and she could feel an embarrassing wetness growing between her legs.

She was not left unattended for long, however, as the ball gag popped out and a tentacle, now leaking cum, thrust its way into Raven's mouth once more. The cock began to pump in and out of her mouth in time with the tentacle molesting Starfire's breasts, and they found a steady, mortifying yet arousing rhythm that awoke something deep inside Raven, a lust that she had always done her best to keep under wraps aside from the occasional venting of steam at the local glory hole or the like. Certainly she had never dreamed of being seen like this by her dearest friend and… oh god. No.

There were cameras in the training room, set to record at all time for reference purposes. Not only were they being violated, they were being filmed.

With this realization, Raven redoubled her efforts to squirm away, but there was no escape from the unrelenting cock that was violating her mouth.

After a few minutes of this, of Raven's mouth and Starfire's tits being violated, the robotic voice over the PA system announced "ROUND ONE: COMPLETE."

And with that, the metal tentacles bulged and flooded Raven's mouth with robo-cum, leaving her no choice but to swallow it all. It was hot and sticky and salty, almost a perfect mimic of the real thing, only there was more of it than any human could produce in one go. Spurt after spurt of it washed down her throat as her eyes rolled back in her head, mind going blank at the sheer sensory overload of the cum flooding her mouth. She did her best to relax her throat, attempting to swallow it as fast as it came, but there was so much of it and some of it broke the weak seal that her lips formed around the cock and cum began to dribble out of her mouth and onto her naked chest.

The cum kept coming, and when it finally stopped Raven realized that her stomach had slightly inflated from the sheer quantity of it all. The tentacle retreated from her mouth, and she burped out a generous dollop of semen.

She finally looked at her friend, and realized that Starfire hadn't fared much better. She was painted in cum from the breasts up, face and hair all sticky and white. The ball-gag popped free from Starfire's mouth and she began to pant frantically, cum-covered breasts heaving.

"Raven, my friend-" she said, but was interrupted once more by an announcement over the PA.

"ROUND TWO: BEGIN."

The inhibitor cuffs lowered the pair to the ground them, forcing them into a doggystyle position with hands and faces almost touching.

"Yes, Star?" Raven said, as gently as possible.

"I-I'm scared," Starfire responded.

"Me too, Star. But don't worry," she stretched out her hands and took Starfire's fingers in hers. "We'll get through this together, okay?"

"Yes," Starfire said, "we will… get through this." She leaned forward and placed a cum-covered peck on Raven's cheek. This innocent gesture, in the face of all that was going on, was enough to make Raven herself blush. She then yelped as a hard, warm metal tentacle probed lightly at the folds of her pussy. From the small shout that Starfire let out, one was doing the same to her.

Raven felt a growing wetness in her pussy, and not just from her slowly-growing horniness. The robotic tentacle was leaking cum as a lubricant, spreading it around her pussy, preparing her for-

"Oh, god!" Raven yelled as the tentacle plunged inside her, invading her tight hole and slowly thrusting in and out. Starfire let out a small moan, showing that one had penetrated her alien pussy as well.

The metal appendage forcefully pumping in and out of her was hard and firm, yet somehow flexible enough to thrust in and out of her with an incredible finesse, stirring up Raven's pussy and riling up a lust inside her. It went to show that Cyborg was a great engineer and programmer, even if he was a damned pervert. Despite the situation, she found herself moaning and bucking her hips slightly, and Starfire was doing the same.

"...Say, Starfire," Raven panted between muffled moans, "what do you say we… make the best… of a bad situation?"

"What-what do you mean, Raven?" Starfire asked.

In answer, Raven drew Starfire into a deep kiss. Starfire's lips were firm at first, her mouth tightening in surprise, but they quickly softened and she let herself fall into the kiss, moaning into Raven's mouth and eventually slipping her tongue inside while the tentacles violated their respective pussies.

Raven responded in kind, caressing Starfire's tongue with her own, and she closed her eyes and let herself be drawn completely into the kiss. Only then did she realize that the inside of her mouth was still coated in robo-cum, but Starfire didn't seem to mind in the slightest. She allowed the cum to coat her mouth too, their tongues entwining as the metal appendages violated them relentlessly.

Gradually, the tentacles began to increase their speed, thrusting faster and deeper inside Raven and Starfire's pussies. The pair's moans became louder and more frantic as the two of them approached their first orgasms at about the same rate - Raven casually observed that the two were rather in sync, and their makeout session had not ceased. Rather, it had only increased in intensity and energy as the two were fucked harder and faster.

Raven broke off the kiss, moaning "Starfire, I'm… I'm about to cum!"

"Me… me too." Starfire panted. "Let us climax together!"

The two of them let out a shout at the same time, yelling "I'm cumming!" as the tentacles violating their holes let out another flood of cum into their respective pussies, filling up their wombs with artificial seed.

The tentacles continued to cum as Raven's vaginal walls clenched down on the metal cock in the throes of her orgasm, filling both of their pussies to the brim - until the pressure became too much and the robotic cocks popped free of their respective holes, a veritable waterfall of cum gushing out of Raven's hole with such force that it sent her over the edge once more, experiencing her second orgasm in as many minutes. From her desperate moans, it sounded to Raven as if Starfire was going through the same pleasure.

Pleasure? She had meant to think ordeal.

She could not deny it any longer, however. For this was pleasurable, and despite not having asked for it she was growing to love it.

"ROUND TWO COMPLETE," the voice declared over the PA, "ROUND THREE BEGINNING."

"So soon?!" Raven yelped, but Starfire moaned her thanks.

"S-Starfire?" Raven asked. She looked into her friend's eyes and saw a frantic abandon in them and a glazed-over look, blinded by pleasure.

The metal tentacles had broken Starfire, and Raven was sure she wouldn't last much longer.

"ROUND THREE. DEPLOYING PUSSY PUMPS AND NIPPLE SUCKERS."

"Oh no," Raven said.

"Oh, god yes!" Starfire responded.