Conversation so far:
who does penny sleep with on the big bang theory
On The Roommate Transmogrification, Raj and Penny slept together.
Who's Raj on The Big Bang Theory?
Rajesh Ramayan Koothrappali, Ph.D. is a fictional character on the CBS television series The Big Bang Theory, portrayed by British Indian actor Kunal Nayyar.
Why did Penny sleep with Raj on The Big Bang Theory?
Penny and Raj become intoxicated and, despite agreeing to remain good friends, end up in bed together.

Question: what happened after the characters slept together
Self-contained rewrite: Then what happened, after Penny and Raj slept together on The Big Bang Theory?