I saw this when I was really little and from what I can remember it looked old enough to be from the 80s or 90s. The two main characters were a boy and a girl both in their teens and the boy was a ghost. I think only the girl could see him and at one point he convinces her he can see through her clothes and for some reason she takes off her shirt. I’m pretty sure they both had black hair or at least dark hair, the boy had shaggy hair and the girl had long hair. And that is about all I can remember. Thanks so much!