Harry Potter

Short story: you heard a rumor that Draco cheat with another girl/boy and you saw it with your own eyes so you asked him to break up. After a while, even you're a Slytherin but you close to Harry. Then bla bla bla, he confessed his feelings and promise to take care of you better than Draco does. One day, you wanted to meet him at his room and you heard some weird noise so you peered slightly at his door. Shocking, that he also cheated on you but with Draco. Why will happen next, it's depends on you. Good luck!