Another word used mostly in The East Coast around MA to describe someone who is creepy or stalkerish. Laggy people are those who follow you around and stop when you stop. They will pretend like they are not stalking you when you talk to them and will talk to you as if you are thier friend.
Person 1: Yo dude that guy over there is watching us.
Person 2: that guy is so laggy
Person 1:Ya dude we better get out of here before he starts following us.