I had an idea based off of this. What about a girl who has been as slave since she was 16, now in her late teens she has done something wrong for her Master and has been send away for punishment and 'repair'. Her new Master has only one purpose and goal. Remind her she is a worthless whore.
Would include most standard BDSM and hard sex as well as watersports, public humiliation and probably just a lot of savage beatings, violence and physical reminders of whose the bitch and whos the boss.
PM me or reply here if interested.