What should she do? (WARNING: EXREMELY LONG)?

One of my best friends, (Let's just call her Celia) has this weird guy crushing on her. (Let's call him Tom.) Okay, so Tom never used to talk to Celia until two weeks ago when this guy asked out Celia for Tom. (BTW Tom is like a really shy guy, who supposedly has a bunch of family problems.) Because Celia didn't really know Tom, she said no, even though the guy tried to persuade her to go out with Tom. So then Tom tried being friends with Celia, which was okay at first, but then he started getting... stalkerish. Like he would wait outside her clrooms for her and follow her everywhere. So Celia started getting creeped out, but she didn't say anything because she didn't want to hurt Tom's feelings. (Celia is one of the nicest people I know.) So she just started avoiding Tom because of the fact that he turned into a stalker. (For example he would run after her when they were in the same cles and for some strange reason he was always there even when they wern't in the same cl.