When Rebecca comes to Epilogue with bruises and an irritated temper, grumbling and griping about people not having any humor whatsoever, Desmond doesn't even need to ask. He just knows a trolling session just went down, and the both of them got the brunt of the ugly side of it.

He has a hard time trying to keep a straight face, but he does it when she's around, then goes into his office to laugh his ass off for a good solid few minutes. God, he loves his job sometimes.