Your sister's always been a little...airheaded. You twice convinced her that the moon got physically smaller through its phases. Twice. But you're a good brother, so when she calls you to come over and help her with something, you head on over...only to find your sister, in a push-up bra and black shorts, hair in braided pigtails. Your sister may be sort of dumb, but she's also really hot. Like, you know you shouldn't think that, but you always have. And here she was, on her bed, looking like an absolute snack. She tells you that her meathead boyfriend Dave is cheating on her, and she needs revenge! So, she wants you to take dirty pictures of her to "anonymously" send to Dave. What?! You're not really sure what this really accomplishes, but you agree. If nothing else, you can see your sister rolling around all sexy on her bed. But when things start, they quickly get out of hand. You know you shouldn't take advantage of how susceptible she is to suggestion, but you can't help it. You have her get on all fours, facing away from you. Then you make her take off her shorts - no panties underneath. Perfect. You take out your cock, which has been hard since the moment you walked in, and position it right at the wet, yawning mouth of her pussy. You tell her to back up, holding your breath and waiting for the fall out. She sinks onto your cock, immediately yelping! When she pulls off, she looks in disbelief at your cock, now coated in her own juices. At first, she's in near-shock: her brother just slipped her his dick! But quickly, the bimbo, revenge-riddled part of her brain takes over. "This would really piss Dave off!" she says, before sliding back onto your cock. You barely need to give her any instruction at all as she bounces on your dick, telling you to do all the things that she never did with Dave. She sucks your cock, taking you deep, then she begs for your cum - the very first load she's ever had, and its from her own brother!