Seriously, you need to approach this kid and tell him to think long and hard about why he's so obsessed with you that he goes out of his way to implicate himself with you. Tell him the truth: "for a dude that supposedly thinks I'm disgusting, you think about me WAAAY too much. You're starting to draw attention to yourself. You should stop before people start to become suspicious."
Then cry, let your bad feelings out. It's better to cry sincerely, than to fake a big smile...
...and once you calm down seek help. There's no problem without a solution, think about it and you'll find the right way to deal with whatever is on your plate ;)