If you have a polyamorous guy who is able to love openly, it could. For those that do enjoy sex, it is as much a bonding process as it is a physiological need. Chemicals of attachment are frequently released, which is what leads to so many friends with benefits situations catching feelings. He is very likely going to bond strongly and have feelings for his sex partner. If you can handle sharing at that level, it might work. But you are going to need a way to work on your own bonds with him, as you won't be leaning into sex as much. You'll both have to put more work into keeping your relationship healthy.