
Apparently, he posted intimate details
of their physical RELATIONSHIP on his blog...
The Big Bang Theory Season 1, Episode 17

...if we should actually engage in coitus
at least one time in our RELATIONSHIP.
The Big Bang Theory Season 4, Episode 5

I'm contractually obligated to make them up
under the terms of the RELATIONSHIP agreement.
The Big Bang Theory Season 8, Episode 3

- Leonard is failing in another RELATIONSHIP.
- He's having problems with Stephanie?
The Big Bang Theory Season 2, Episode 9

Well, if you had
a physical RELATIONSHIP,
The Big Bang Theory Season 5, Episode 23