Alan gets jealous when Charlie bonds with his girlfriend, Lyndsey, on the upcoming Two and a Half Men.
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Two and a Half Men Season 8 Episode 13 Quotes

Lyndsey: Oh, God. You saw "Cinnamon's Buns?"
Charlie: Not all the way through. Though I'm very familiar with the bakery shop scene in the middle. You know, with the frosting gun?

Charlie: Wow, you really missed the signals.
Alan: What signals?
Charlie: For me it was her taking off her sweater and saying, "Quick do me before Alan gets back from his trumpet lesson."