Peter and Lois spend the entire day in bed on Valentine's day on Family Guy. "Valentine's Day in Quahog" is the 13th episode of the show's 11th season.
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Family Guy Season 11 Episode 12 Quotes

Lois: Peter, are you ready for your Valentine's gift? [drops trenchcoat, is naked]
Stewie: No, but I'm ready for therapy.

Lois: You know, Peter, since it's Valentine's Day, I was thinking let's do something we've never done before.
Peter: Release the virus?