Will Walden decide that it's time to come clean with Kate on Two and a Half Men. "Grab a Feather and Get in Line" is the 13th episode of the show's tenth season.
Added:

Two and a Half Men Season 10 Episode 13 Quotes

My penis is like Santa Claus, I don't have to see it, I just need to believe it exists.

Walden

Kate: This whole time, I thought he was the douche, but turns out, you are the douche.
Alan: Unbelievable! She likes me.