Responses
Philip is the guy he was stuck in space with, based on some context clues I think there was nothing physical between them, only reliability(because when the two main characters where getting freaky, Sahan said he hasn’t been with someone in a long time). My guess is Sahan’s ex assaulted him in some way which is why he reacted that way when getting the BJ.

Is that the guy who hurt sahan? And is that the same guy he was in space with that was depressed? Also why did he look so happy to hear from him if it is..I might need to reread this