It just wasn't enough to cuckold you and take your hot girlfriend from you - he wanted to go even further than you could ever have imagined. I mean when he insisted that you were no longer allowed to fuck me - I thought he was being as mean to you as he'd ever get. Then banishing you from our bedroom altogether - making you rest in the spare room - nowhere near your own girlfriend. It must have been hard on you - kissing me goodnight and then obediently heading for the spare room as 'master' had commanded. He totally cock-blocked you from your own girlfriend so that he gets me all to himself. I guess I missed you, but I always knew he was just a phone-call away if I ever got 'lonely'.
Next came the chastity device - that was kinda cruel of him, I guess. You lost all access to your girlfriend's pussy and then you lost access to your own cock. He sent me the lock and I snapped it shut, trapping you inside that teeny-tiny device - that must have been so humiliating for you - watching your cock getting caged away so that you'll never get to fuck your girlfriend again. Now I could wear all the pretty lingerie and cute little outfits master loves so much without you getting a little cucky-boner! Now there would be no way you could ever jerk off to 'Masters' girl. Now there could be no cheating - master knows you can't fuck me anymore even if I let you!
I guess after that, you thought it couldn't get any worse for you huh cuckold - I mean what else could he take from you? And then boom! He tells you you're going to be gay. It's not enough for him to take your girlfriend, banish you from the bedroom and lock you in chastity - he wants to take your sexuality from you too. He wants to turn you gay. He's going to make you suck cock cuckold. His cock, his friend's cocks, stranger's cocks - however many it takes for you to accept that's all you'll ever get from now on. You won't ever experience sexual pleasure with a girl again - you will only experience cock.