Buddy Troll

Buddy troll =

Person who is friends with somebody not because they support them as a person, but because they think they are funny or interesting.

This can sometimes be assholish, or harmless depending on how invested a person is in the friendship, and how much they respect the individual as a human being and not an exhibit.

And how much the individual being "buddy trolled" cares.

Friend: "You know Josh is a buddy troll right? He is only talking to you because you do stupid shit like build Lego dicks and ask random girls out, and he thinks thats funny."

Josh "Aughuh! And I'll fuckin do it again!"