Weird dude keeps following my friendgroup at school

So basically theres this lonely dude in my form, he kinda lurks around me and my friend group but doesn't talk to us and just says "hi" to me sometimes (and i say hi back because im polite). I don't wanna be the kind who's like "ooohhh he stood in the same place as us he must be following us" but my whole friendgroup is noticing too, i wouldnt say its stalker level but it is a little creepy. I also talked to him about demon slayer in my form ONCE so idk if thats important. yesterday my year group had a school trip to some university and i was talking to me friend but the weird guy just kinda kept intruding in our convo and kept saying things and i dont wanna be mean but nobody was talking to you dude, my friend says he (probably) has a crush on her which could be true but idk im just gonna blindly believe her cus shes smart. anyway so lmk if hes being weird or if im just being paranoid and rude