3-Way Tie
I haven't written one lately, but I remember struggling with pronouns in a three-way scene. Be very careful with antecedents or your reader won't be able to 'see' what's happening.
Another caution, depending on how graphic and how realistic you're trying to be, is positioning. Try hard to remember these are people, not athletes and certainly not contortionists. I have been known to draw stick figures to help me figure out whether Person C's arm is in the way of Person A's leg, or whether Tab B can enter Slot C in this position.
The only cliche that comes to mind in a threesome scene is if the two of the same gender, in your case the men, are straight when the scene begins, and by its end they're bisexual. I've seen numerous, uniformly ludicrous, attempts to have a three-way romp change characters' sexual orientation, and it just ruins it.
BTW, there's not one, not two, but three calls for erotica in a paying markets section. Check it out!
Maryn