In private, Trevor offered up his pants to the new guy, as well as his boxers so his"boys" wouldn't touch his new suit. He then re-entered the room where his pals were without pants and dropped his big lie:"Guess who just had sex with a hot limo driver!" This was mere moments before his death.
But as it turns out, at least in that one moment, Trevor was a good person. Maybe even a better person than he gives himself credit for in his ghostly existence. He's certainly better than his bro pals. He also got some satisfactory revenge on the leader of the bros. The whole story came about because the living couple in the mansion, Sam and Jay, decide to sell the timepiece on ghost Hetty's husband's corpse to help them keep their B&B dreams afloat. The person they wound up deal with was head bro Ari.
When Trevor innocently tries to get Sam to bring him up to his old pal -- before he knows the truth about that day -- Ari makes everyone suspicious by freaking out and making a secretive phone call wondering if he's being blackmailed . In the end, Sasappris helps Trevor pull a good haunt on Ari with a note in the same drawer the bros used to keep their drugs reading,"I know what you did," signed"T. Money." Ari offers double the asking price for the timepiece if Sam and Jay if they'll never speak of any of this again. So it looks like Trevor's loss is a win for the whole household.