Perverted teacher

There's a student teacher at my school and he's a sub so we see him some days and not others. He doesn't really say his name or teach. He very strange. I told my friend ab him and she said he looks familiar then I asked if he checks out other girls at her school and she said yes.

Should I report him? He's young like in his 20's and he acts strange. I liked him Bc of how he looks and I could tell he's shy.

I know it's true just me that'll find this odd ab a teacher. Maybe it's some sort of fantasy of his. I don't want it to go too far.