After betraying their master by unlocking their chastity cage without permission they've given a new role as punishment. 

I enjoyed writing this, it's an idea that always excites me and hopefully get to experience one day, locked away and made to fuck and pleasure another with an unfeeling strapon, one larger and better than my own. It just seems like it would be an amazing mind fuck and humiliation, desperately fucking them to orgasm while my own cock goes untouched and strains painfully in its small and cramped cage.