Mickey says "you didn't make HIM wear a rubber", meaning the other guy topped. And we only saw a few scenes of Gallavich sex that made it on air, I'm sure there were plenty of opportunities for them to switch up during implied off screen canon, hence the line "last night's bottom" .

I think it was pretty awful that Ian clearly didn't want to have sex but he forced himself to go through with it anyway. The whole Trevor arc has been Trevor aggressively insisting they should have sex and everyone including Trevor telling Ian they can't "just" be friends. The sex scene itself seemed to be written…

Myles-Ian bottoming in the porno in Season 5 was what made Mickey finally realize Ian needed professional help. (Also Ian calling Mickey "last night's" bottom in Season 3 strongly indicated there were other nights where Ian bottomed. ) The show once again cutting away from a female-free sex scene…I can't think of a…