I think if you are going to the trouble and public expense of creating a coroners case, the realistic scene would show a hot str8 guy wanking off in a hotel watching porn. The garrote is slipped over his head before he knows he is in danger. After he is weakened, then he can be fucked and strangled like a cheap rag doll.
Of course he is turned on by every bit of this and he stays hard the whole time. The camera captures every hot movement of his struggles, and the precum that betrays his enjoyment. At a certain moment the victim realizes that the cock raping his ass feels good, real good. Maybe he regrets never trying sex with a guy before. But one thing is certain, as the garrote does it's work, his cock gets harder and harder until it explodes with the biggest load of cum he ever felt. He smiles as his body is suddenly satisfied. There is no need to struggle. He has never felt better as he feels the sensation of hot cum flooding his insides.