Sheldon has a bladder emergency from an over-sized banana smoothie and goes into the bathroom while Leonard is showering. Only Leonard is not showering alone; he is with Priya.

In response to the bathroom situation, Sheldon says that Leonard violated the roommate agreement. Luckily for Leonard, he now has a lawyer for a girlfriend who favorably argues the claim in his favor.

Due to the complicated terms of the roommate agreement, the boys no longer have to have Pizza night Thursday, so they order Greek food. Sheldon leaves upset and goes to Penny's for pizza night, but she is has a girls' night out planned. He decides to go with her.

The girls get drunk, including Amy, who flirts with Sheldon. Sheldon admits to never being kissed. When Amy offers to experiment with him, he turns her down, so she plants a kiss on Penny.

The girls and Sheldon decide to go dancing. Afterwards, Sheldon accompanies Amy home for a Yoo-Hoo night cap. Amy has a smoking monkey. She convinces Sheldon to fight dirty to reinstate the roommate agreement. She kisses him and then goes to the bathroom to puke.

Sheldon blackmails Leonard into signing a new roommate agreement by threatening to send an email to Priya's parents about her relationship with Leonard.

Sheldon and Amy decide to pretend the previous evening never happened and continue their relationship