Who needs human companionship?!? Not Sheldon, this character hopes, on the episode titled "The Zazzy Substitution."
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The Big Bang Theory Season 4 Episode 3 Quotes

Wolowitz: Women, huh? Can't live with 'em; can't successfully refute their hypotheses.
Sheldon: Amen to that.

Leonard: Amy is judgmental, sanctimonious, and frankly just obnoxious
Sheldon: So?
Leonard: So we already have you for all that.