This is a crack fic with mature sex scene(s)!

Fifteen-year-old Timmy is bored. He's left with Cosmo while Wanda and Poof are out for a few days. Cosmo is tossing out ideas for them to have fun.

"Wanna go on a roller coaster?"

Timmy shakes his head. "Did that yesterday."

"Wanna have a chocolate slide?"

Timmy frowns. "Last I did that Remy thought I shat my pants."

"So?" Cosmo shrugs.

"No."

"Wanna go to a Chip Skylark concert?"

Timmy rolls his eyes. "He's four years ago."

"Want me to summon anti-me?"

"I… yeah!" Timmy's eyes brighten.

Cosmo grins as well. "Okay!"

Without putting much thought into it, Cosmo raises his wand and summons Anti-Cosmo to the bedroom. Unfortunately, Anti-Cosmo is busy fucking Anti-Wanda when called. His claws are dug into her shoulders, so they come into the bedroom as one. Timmy shields his eyes and Cosmo jumps into his fishbowl. Timmy throws a blanket from his bed over them. Anti-Cosmo notices, of course, but is busy. When she collapses, Anti-Cosmo uses his wand to bring in a chained Anti-Cupid. Anti-Cosmo moves on from an exhausted Anti-Wanda to a resentful yet resigned Anti-Cupid. Anti-Cosmo fucks him while still chained up. Anti-Wanda watches.

Even after this, Anti-Cosmo isn't satisfied. His libido doesn't run too long, but when it does, he needs to drive it out. He shatters the fishbowl. Cosmo turns to his regular self to escape, and his counterpart grabs him to fuck him. Timmy is watching, horrified, feeling stuck to the bed. Then he realizes he is literally stuck to his bed. Literally. He shuts his eyes, not baring to watch. Anti-Cosmo is tired after this, but he still has a while to go. With Timmy lying there almost in wait, Anti-Cosmo uses this. He fucks Timmy. Halfway there, Timmy comes, and Anti-Cosmo finally comes.

Anti-Cosmo is more exhausted than everyone. His libido has finally tired out. Anti-Cupid is bleeding from the claw marks and restraints. Anti-Wanda and Cosmo are bleeding from claw marks and vampire bites. Timmy is bleeding due to being a virgin. Eventually, Anti-Cosmo stirs and cleans himself up.

"Now then. Why was I summoned from my castle during intimate manners?"

Timmy gawks at him, breathing heavily. "Are you fucking kidding me?"

Anti-Cosmo smirks devilishly. "Why, Timothy. Did you want another fuck?"

Timmy pales at the bluntness of the proper evil gentleman. He's on the edge of the foot of the bed now, polishing his monocle.

Timmy coughs. "You just start screwing with everyone. Aren't you married?"

"Of course." He puts his monocle back in place. "What has that to do with anything?"

"Um, everything! You're cheating on her."

"Naw he ain't." Anti-Wanda responds.

"You're… not?" Timmy tilts his head, shifting slightly.

Anti-Cosmo tuts. "I'm not so callous, young Timothy. We have an open marriage for instances such as when our libidos hit their breaking point."

"Uh…"

Anti-Cosmo sighs. "On average, I simply trap several anti-fairies who owe debts to me. I fuck them unconscious. This was indeed an alternative experience. I have fucked other fairies before, my counterpart included, alas – it has been over a century. A godchild, though, you are my… second."

"Second?"

"Don't sound so put off, Timothy. The first was dear Clarisse, in 1692."

"What happened?" He genuinely wants to know.

"She had my seed flowing inside and people burned her as a witch."

Timmy is taken aback by the sinister tone the conversation has brought. Anti-Cosmo somehow sounds affectionate yet dangerous.

Anti-Cosmo clears his throat. "You are my first male godchild."

"Wow."

"You should feel honored, Timothy. I don't fuck just anyone."

"Yaw wanna fuck 'im, 'gain Beaver Boy?"

Timmy's eyes widen. "What?"

Anti-Cosmo answers for the teenager. "Splendid, dearest."

Anti-Cosmo chains his counterpart akin to Anti-Cupid to watch him fuck Timmy again.