Sheldon and Penny are getting on each other's nerves, and Sheldon tries to use operant conditioning on her. Howard and Raj dress up as goths to try and score.
- Actor Allusion: After Penny mentions an anecdote about her work, Sheldon says, "Oh, Penny, it's as if The Cheesecake Factory was run by witches." Kaley Cuoco had just been on the last season of the TV show "Charmed."
- Catchphrase: More to show the character's emo-ness than something quotable. "Not that anyone cares."
- Food as Bribe: Sheldon is secretly conditioning Penny by offering her chocolates whenever she does something he approves of.
- Getting Crap Past the Radar: Raj whispers something to Howard after Penny acts bossy towards Leonard.Howard: Yes, she's pushy, and yes, he's whipped, but that's not the expression.
- Morning Routine: Penny makes French toast on oatmeal day. It doesn't go well.
- Perky Goth: The sort of goth Raj makes, of course.
- Squick: Howard's mother won't see the tattoo on his butt...because she takes his temperature orally now.