hucklerobby cheating headcanon:
dennis and robby have a pretty bad fight that ends with dennis leaving home and going to a pub with Santos. Robby in his autosabotage thoughts is convinced that Dennis is gonna cheat with some hot random dude in a gay bar so he decides to cheat first with someone Robby knows that Dennis is fondly jealous of and gives him a lot of insecurities, Langdon. Frank is desesperate for Robby validation and being the golden boy again so he agrees without a thought. Robby goes to Frank's new apartment and spends the night there just to wake up to Dennis messages asking where he is and apologising for leaving with Santos and not staying to fix the things.
I think Robby would feel so bad that this triggers his thoughts of going to the sabbatical, to try to get away of what he did and avoid accountability, Dennis still hasn't find out about the Langdon thing so he thinks Robby is trying to push him away.
bonus:
Robby who always bottoms, decides to fuck Frank from behind so he can imagine it's Dennis and convince himself that he's doing nothing wrong.
