The point is to make him think that he might be servicing one or more of your guests as well, but he has no idea. It's humiliating and very powerful mind-play.
Since he can't hear or see you, you can setting his expectations before hand is a very big part of this. Before you start, make him dress in something Sissy-ish, and tell he needs to look really good and cute, and warn him that he cannot in anyway disappoint...he really needs to give the best oral pleasure! Tell him you want your guests to be very happy! If you really want to play with his mind and you have an open minded girlfriend willing to help, go together to touch him or tickly him with several hands so he can feel more than 2 hands at once, and he knows for sure someone else is there.
You can tease him for a long time afterwards, as he'll never know if he was servicing someone else as well or who..... you may want to have your girlfriends giggle and "thank" him next time they see him, or send a text message or email that he can see them saying they "enjoyed his attention, and will be sending you the photo" (you can even fabricate this by sending a fake text). He'll never know if it was real or not, and this will be so humiliating and so erotic
Since he can't see or hear anything, you can play with him by one time making him lick you directly, another time through your panties, or another tie through your stockings or pants… each time applying a different perfume so he thinks it could be a different person.
Do this just before you are expecting guests, or when you have guests over who are girlfriends that he knows are open minded and cruel. Alternatively, you can set up the whole scenario and not have any guests at all, as long as you make him think you were having guests by pretending to invite them and then leaving a few empty glasses of champagne or coffee around with visible lipstick stains on them for him to see after you release him...
The best way to set this up is to invite some open-minded girlfriends over and make him know they will be coming. They really don’t have to know what's going on at all if you don't want them to,..it's just so he thinks he's been publically exposed. If you are able to get your girlfriends to tease him indirectly afterwards, it will give him extraordinary erotic mind play through humiliation for a long time afterwards which will be firmly in your control.
It’s the preparation before, and the teasing afterwards that will make all the difference. If you fail to prepare him before or tease him afterwards, you’ll miss out on the most erotic humiliation of this scenario… this is purely psychological. Make sure the blindfold is very secure and he can't see, and make sure you strap on his headphones in a way that they cannot fall off and put very loud music so it's impossible for him to hear...very important!