What level of overly attached is it?

Then he'll be like "why do hot girls always go for the guys that treat her bad, why can't she go out with nice guys like me"

When that happens you tell him you'll give him God's number so he can save his soul from eternal damnation and hellfire. Worked for me anyways.

Psychotic attachment

Has anyone noticed the way the response is written, the creep wants the boyfriend for himself?

Just block his number? Duh..