A very gullible individual or "sucker".
A Chupa Chup also refers to someone who is exceedingly stingy when it come to hooking it up with bitches; for either fear of losing his delicious lady candy to his friends, or a big headed belief that he will be able to get at his lady friends without help from his friends whom he knows to be ballin' ass cocksmen.
Yo Darnell! Why the fuck didn't you tell us those girls from your Japanese class were coming over while we were conveniently out watching Spiderman 3! We have been asking you to plug us into the Asian pipline for weeks you dick! You are such a throbbing Chupa Chup!