eh, if he's not gonna do it then he's not gonna do it. Other than reiterating to him what a turn on it is for you, there isn't much else you can do. You can't force someone to do something against their will like that, you can only try to convince them of hte merits
Give up. You can't force someone to share your kink. Either accept that your boyfriend will probably not change his mind or find a new relationship with someone who will cater to your desires.