Thanks for this Q! As a general rule (some friends or permission-askers exempted) I usually prefer things were kept just suggestive, and not explicit NSFW, when it comes to art of my guys. To clarify:
A-OK: topless/flirty nudity, general suggestiveness.
NO TY: explicit sex acts, really front & centre nudity, fetish stuff.
Feel free to ask if ur not sure!