AU / Buffy is a good girl and Spike has a reputation of a player. At some party Angel is cheating on Buffy with Dru. She catches him, then ends up with Spike (they're having sex at the beach?). Dru takes naked pictures of Buffy with Spike, and shows them at the school. At first Buffy suspects it's Spike's doing (bad boy image, she's latest conquest). They got in trouble with principal Snyder. Angel is stalkerish and jealous - shows compromising picture to Joyce. Buffy keeps seeing Spike.
I'm also looking for a fic with evil Spike, who is somehow with Scoobies and at some point pretends he wants his soul back (but really he just wants to be free and plans to escape and is only stalling them). I think it happens while Scoobies are trying to curse Angelus again, and it gives him the idea. Internally he's affraid of being souled and it's only his survival instinct to pretend so. Buffy is into it - she buys the act. I think they don't have enough ingredients for using on two vampires so it works - Spike escapes and Buffy is dissapointed that he lied (he was perceived as an ally?). It's not the main plot of the story but it's all I remeber.