Charlie goes on a date with his dermatologist, Michelle (Liz Vassey), and everything goes well until he learns her age... 47.  Alan convinces him that age is just a number, he tries again, but then discovers she has a hot, bisexual 20 year old daughter, Shauna (Krista Kalmus).  Realizing that one day he'll sleep with the daughter, he breaks up with Michelle (using Chelsea as his excuse), only to discover the daughter thinks that 35 is old and creepy.

Alan, meanwhile, keeps masturbating all around the house in weird locations.  At the end of the episode, it's revealed Alan had an extra boner pill about to expire, but no woman to take advantage of it with so he took it anyway.