The Champ

S2 E6: When manipulative moms Marly and Lindsay convince Christine to serve hot lunch at Ritchie's school, Christine finds herself serving with Stan (recurring guest star Andy Richter), also known as "Sad Dad," and she finally admits why she's so attracted to him. After Matthew's date from the previous night shows no intention of ever leaving, Christine decides that she and Matthew must take control of their dating lives, and she vows never to sleep with Stan again.