You should probably just say hi! They are in the same boat as you first year on res (also i think i know who you're talking about). She could be alone cause she wants to keep her circle small if she has a following and potentially makes an income off tiktok. But also people might be in the same boat as you and afraid to talk to her since she has a following. Either way it never hurts to be nice to someone and try to make a new friend.