Tycho gave a short, scoffing, "ha" because the very idea was laughable. On top of their mutual agreement of exclusivity... he liked to think he kept Ford very satisfied in that regard. Besides even if Ford was secretly inclined to sometimes sleep with others, Ford was hardly the "have sex in a balls empty room" type of person, Tycho knew that fact all too well. It was because he knew Ford and how their own relationship was set that he had such a hard time making sense of any of this.

"Why were you in a dark room with a lady in an undone dress. And for such a length of time?" He still did not think Ford had betrayed him - Ford just would not do that - but what had he been doing? What explanations could there possibly even be? He was perhaps one of the most imaginative person in existence but all the scenarios presented to him by said imagination seemed equally implausible.