1x13 - Ruby Gloom

Skull Boy puts on a magical hat that makes him talk like a Shakespearean actor which makes Iris and Misery fall in love with him. In fact, they love Skull Boy so much that they won't stop stalking him. Skull Boy then goes to Ruby and asks her to help him figure out a way to make the other girls leave him alone. But then, Iris and Misery see Skull Boy spending a lot of time with Ruby and they start thinking that she is what Skull Boy likes in a girl and they both start acting like Ruby. (From: http://rubygloom.wikia.com/)