Sheldon: Hello, home wrecker.
Penny: What did I do?
Sheldon: You gave Leonard somewhere to go. Thanks to you, Amy's out buying his and hers bath towels. Like I'd ever dry myself with something that has a possessive pronoun on it.

Penny: I love him. This is just happening too fast.
Sheldon: You think this is fast? It's just a matter of time before I see Amy's leg stubble in my shower.
Penny: Yeah, and I've seen those legs. You might want to get some Drano.

Sheldon: It's Penny's fault.
Amy: What?
Sheldon: She doesn't want to live with Leonard, so he has to come live here again. She's the snake in our garden. She's the reason we can't be happy.