In that scenario I'd like him being led into a livestyle of nearly 24/7 bondage and made to be veiled in an afghan burka all the time, where no features of his face and body are visible at any time and his bonds are hidden by the veils
How this comes to pass and how he reacts to being a bound burka boy, that's up to you

It doesnt need to be sexual, most important is that one of the guys is made to wear burka and maybe has no access to his regular clothes anymore