Complex sentence: George Sr. does it to Cindy in Alter Egos and Shack and Aww and in the very beginning of this episode, when he takes off his shirt, G.O.B. says "I'm still kind of tweaking my nipples," referring to his new magic trick.
Split into simpler sentences: George Sr. does it to Cindy in Alter Egos and Shack and Aww. And in the very beginning of this episode, when he takes off his shirt, G.O.B. says "I'm still kind of tweaking my nipples," referring to his new magic trick.