my friends obsession w this girl

it’s really freaky bc he’s a good guy and everything (truly) but it’s just so creepy. he never stops talking about her, knows everything in her life, and is in general real weird about her, despite talking to her like three times in his life. he’s probably got her whole schedule memorized, even though she’s only in 3(?) of our classes. he’s kinda strange about people who date her, and even has the whole ‘you don’t deserve her, ill treat her better’ spiel going on too. it’s scary bc he’s literally the best person i know and this behavior is so unlike him. idk, the whole situation just rubs me the wrong way :/