Ultraboy can't stop himself from cumming....

Ultraboy whimpers as he feels his prostate being deliberately targeted by the dominant futa behind him, he can't help the feeling of euphoria washing over him as Nishi reaches round and starts jerking him off.

"Oooh FUCK!" Screamed Ultraboy as Nishi sped up her thrusting whilst simultaneously increasing her whacking off of Ultraboy's rapidly swelling member.

Ultraboy started to smile as he feels his mind starting to accept his fate. His body didn't take long to follow suit, quickly matching Nishi's rhythm, him pushing back as she pushed forwards.

Five minutes passed before Ultraboy felt his balls start tightening, seconds later he froze and grunted as his cock spewed its load all over the floor in front of him.

Nishi paused her thrusting as Ultraboy's asshole tightened almost painfully around her cock. Once she felt the hole relax again she started thrusting again and smiled as she watched Ultraboy's chest slowly expand to a B cup whilst his hair started growing at the same time.

Ultraboy groaned in pain as he felt his insides altering to accommodate his new womb and ovaries. Nishi saw the discomfort and knew that the time was now, with one hard and deep final thrust, Nishi roared out her climax, her cum splattering all over Ultraboy's bowels. As soon as Nishi pulled out, she laughed as Ultraboy screamed out in pain again as his new vagina nestled itself behind his ballsack.