Nerd vs Cock/Vagina!!!

Well here's what I was thinking. Let's say the older sibling, boy or girl, is the jock. And jocks go to parties and drink and sleep around. But this character is failing senior year they need to pass for their scholarship. the smartest person they know is their younger sibling who is a big time nerd, chess club, band, Yada yada. But the young sibling hates their older siblings popularity attitude lifestyle almost everything about them. And refuses to help. Desperate, not to brainy jocks make mistakes and makes a very wrong sexual decision......or was it the right one?