By the time Emu was in good harmony with his lifelong mate, Sento was in his personal laboratory. He had been working on the Evolt genetics inside the garden of alien botany, and was close to the most stunning discovery ever found.

"Evolt Junior?!" Sento was puzzled.

"Yo!" A voice came in made Sento startled.

In shock, Sento turned back to look at the mystery figure, who was now grinning, hiding how amused he really was.

"You like it?" The stranger asked meekly, eyes darting down over Sento's shoulder to look at him.

How was he going reply to that? What should he say? What could he say? In front of Sento, it was Another Build, the red-blue horror bearing the same identity of Kamen Rider Build but in an eldritch manner that was closer to a monster. Sento was not so lonely with Another Build. There were Another Ex-Aid and Another Ghost, both of whom were wicked duplicates of the original Kamen Rider counterparts in terms of appearance and personality. Their snarling mouths and hideous eyes were so terrifying to see, so fathomable that just even the slightest glance of them was enough to give chills and nightmares.

Sento's silence didn't stop the Another Riders at all; they gathered around him, their hands smoothed over his hips and then up to his chest, beginning to unzip his jacket.

"Don't wait," Another Build mumbled, lips warm against Sento's, "he's ready for you."

Sento's attention shifted, turning back to look down at Another Build, who was grasping his balls and started squeezing. Another Ex-Aid and Another Ghost kept the genius physicist at both sides to prevent him from escaping. They lifted his T-shirt upwards to reveal his bare chest and belly, before lifting the jacket and the T-shirt out from his body. Another Build unzipped Sento's pants and pulled it down, before exposing his hidden package beneath his undergarments.

"So cold..." Sento whines as he stood topless and stripped of his clothes.

"No, you know you certainly can't leave." Another Ghost screeched into Sento's ear.

Sento's head fell back with a groan when Another Build finally wrapped his fingers around his cock, thumb swiping over the slit of his cock to smear the pre-cum beading up there. Sento started grunting as he thrusted his hips forward into the tight circle of the monstrosity's hand. He felt lips on the back of his neck, a soft eerie touch that he had felt more than enough times in bed before with Banjou. But this sense of touch brought him more terror than pleasure, as the Another Riders had creepy-looking teeth and low-pitched grunts.

"I'm not going to make it... My fate is sealed... I am so desperate for a good escape..." Thoughts clouded Sento's bright mind like a dark storm.

No matter how hard he tried to brainstorm his way to freedom, he was unable to resist the ever-escalating temptation of lust given by the monstrous versions of Kamen Riders. Sento was incredibly hot inside, his fakery's teasing fingertips twisted softly at his most sensitive privacy next to him but it seemed he couldn't move them anymore than that.

"You're no longer be able to escape. No matter how you beg for your own safety, your destiny is written on the stars. We're here to decide what to be for you." The Another Riders said.

Sento was like a rabbit trapped inside three wolves' paws and unable to escape or resist. Another Build sucked Sento's cock just after Sento sat on the floor to receive an oral penetration from Another Ex-Aid and Another Ghost.

"Look who's here for the day." A hulking monster resembling a heavily altered Kamen Rider Zi-O beyond recognition arrived to the fray.

His voice sounded rough, and it was clear that he was an evil counterpart to the original Zi-O, the young man with a wish of being a king.

"Huh?! Four on one?! Am I a joke to you guys?!" Sento frowned.

"No way, fool." Another Zi-O grabbed Sento's hair.

Eventually, Sento's normal angry voice was reduced to a small breathless voice as the creatures started giving him a violent thrashing with their manhoods. Dick after dick, cock after cock, Sento's mouth was thrust straight into the back of the throat.

When Sento was unable to resist, the Another Riders forced him to stand on all fours and one by one they drove their hard sticks into Sento's ass in a fast pace. Sento's feet shift on the floor, legs slightly parting more as Another Build penetrated into him. He was rough and careless, something primal in his head telling him to play with Sento hard enough he would feel it later, that he would have marks. Marks the other Another Riders would see later, be able to see how good Sento got it.

Sento moaned from the other side, speaking between gasps: "Th-this isn't what I- nngh! Expected when- aH! When Banjou asked if I would p-pitch in for a-ahh- a birthday present!"

The end of his explanation tapered off into a keen, Sento's knees wobbling dangerously as Another Build ground his cockhead into his prostate. His fingers held onto hips tighter, giving him a better hold as he played him harder. Banjou would never invite the freaks to the party, but he had been absent right before Another Build took his flock in. The copulation between the beautiful science genius and the four beastly humanoids had reached midways after 20 minutes had passed since Another Build entered Sento's house, but it was still not done.

For a moment Sento's vision tunneled and went blue, fading out to a dark blurry mess. His heart began to race and something kicked back inside of him. Distantly he was aware of Another Zi-O trying to push his orgasm into him without taking a little break. His pleas fall on deaf ears. The monster's rough skin slapped against Sento's fairly smooth buttocks skin as Sento lay on his back with legs parted and spread outwards.

"Little rabbit, little rabbit. You're our pet, our one and only pet." Another Zi-O and his bad guys chanted a mantra over and over until Sento was very very weary.

One hour had passed, Sento had been fucked past the point of exhaustion. He hung his head, watched sweat drop down to the floor as he panted. If he just had one of his hands free he wouldn't be so tired, his core wouldn't be burning like it was now. It hurt to not have something to lean his weight on, and he was like a loose sack of meat thrown on the floor. Still, Banjou had not returned home.

"No way, folks. We have came a lot on this rabbit's body, inside and outside. He was like a fat bunny." Another Ex-Aid moaned.

"Ooh, stop your whining melody, please. He was so skinny that you can feel nothing but bones and skin. We're so regretful about our foolishness to choose this bunny for food." Another Ghost said.

"Heh? You two are both out of context. He still has meat inside, but very small. You can even gulp him whole with one bite. Really yummy." Another Build replied.

"Now. Stop arguing and get out of here." Another Zi-O said to his peers.

"Why not taking him with us?"Another Ghost asked.

"No more dumb questions and leave him alone. Darn." Another Zi-O said.

The Another Riders decided to leave Sento lying alone in a messy pool of cum from them and himself.

"It would be better to take you along with me." Another Build snatched Sento out and escaped with his gang.

Banjou returned home with a birthday gift for Sento but did not get a trace of him after he disappeared. Banjou was puzzled by the reason for that Sento was absent. He was also unsure if his friend was safe.