Ricky Spanish is doing some homework about male sexuality. He's just reaching the part where he is writing notes about a man being able to hold back on cumming when his stepsister, Cielo West, comes up behind him and sees what he's writing. Cielo claims that Ricky is wrong, that guys can't control themselves with their minds. She eventually insists that Ricky prove it. Ricky tries to tell Cielo that she's his stepsister, so he can't even get hard for her. That just lays down an even bigger challenge for Cielo.Pulling up her miniskirt to show off her thong, Cielo teases Ricky with her bottom. Then she turns around and pops her titties from her shirt. Eventually, Ricky gets a boner just as Cielo had hoped. He doubles down that he can still control his cum, so Cielo gets on her back and rubs her pussy in an invitation for Ricky to give it to her and show that he's right. Ricky is only human, so with that much urging he's happy enough to stick it into his stepsis. Cielo pulls out every trick in her book to try to make Ricky cum. She sucks his cock and balls in a lusty BJ. Then she climbs on top of him and rides him in cowgirl while rubbing her clit so her orgasm can milk Ricky's shaft. Ricky is feeling pretty confident now, so he gets Cielo up on her hands and knees and fucks her in doggy as Cielo rocks back to meet every stroke. Ricky does manage to hold out for a bit, but eventually he gets too close and knows he needs to pop. That's when Cielo rocks back and keeps him inside her so that he delivers the creampie she was after from the start of their argument. Ricky is unhappy that Cielo got him to bust a nut inside her, but Cielo couldn't be happier.