They humiliate him more...

„Listen to those moans, mom” Said Ultimagirl, fucking Ultraboy’s ass with deep thrusts “They’re so girly, don’t you think?”
“Yes, very interesting indeed” Ultimamom approached them, looking into Ultraboy’s ashamed face. He couldn’t hide his arousal, no matter how hard he tried.
“You body isn’t lying, sweetie” she smiled “Not a real man could moan like this while being fucked in the ass. This means you’re not a man at all”
“But I’m…”
“Oh, shut up!” Ultimagirl slapped his ass with her palm “None asks you!”. She increased the speed of fucking him, turning his words into loud moans again.
“Oh, don’t be cruel for our little girl, daughter” Ultimamom’s finger moved around Ultraboy’s lips, all red thanks to the lipstick they applied previously “You’ll make her cry.”
“I’m gonna make her cry!” shouted Ultimagirl, thrusting herosplitter as deep as she could, causing Ultraboy to cry from pain “Now, you can speak! Tell us that you always wanted to be a girl!”
When Ultraboy said nothing in answer, Ultimagirl squeezed his dick in her hand. He produced another loud cry.
“Aieeee!!!!! Yes… I always…. wanted to be… ohhhh!!! girl…!!!!” he said, having his ass fucked in the most brutal way.
“See, mom?” Ultimagirl smiled “It’s so easy to make her telling the truth!”