Guest Star: Briana Cuoco

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  The Tangible Affection Proof
  Season 6, Episode 16 - Aired February 14, 2013

  Leonard and Penny go on a double date with Howard and Bernadette on Valentine's Day, while Sheldon and Amy search for the perfect presents for each other. Meanwhile, Raj and Stuart throw a party for single people at the comic book store.

  Appeared as Gretchen