Some guy I hate so much is going back to my class. He might not know my crush yet, but I'm afraid that he'll do everything to screw my life as soon as my other mates (who are old friends of him) tell him their rumors about me loving her. Using excuses to hide anything won't be enough for me, I guess
It sounds like it might be in your best interest to intervene before he does. If you talk to her and make a significant move then you can control the outcome of how she sees you. Plus if this guy is as wicked as you say he might be then it's best to avoid him at all costs.