If you are going to continue working after you enter into an exclusive relationship with him, you really have to tell him. He has the right to know if you are having sex with other men for safety reasons if nothing else. Even with condoms, there is still a risk of some STDs. Not to mention honesty. If he's the right guy for you, the. This is something you can work out. If he is not okay with it-- and you are not willing to give it up-- then the two of you just aren't the right fit for each other.