I know a few, but they have different motives. Sometimes, it's client hoarding with no real connection; sometimes, it's a social thing; sometimes, it's found best in poly relationships, but it's not presented as a stable.

I have regular clients who I also view as friends, but I don't forbid them to see anyone else. Personal slaves came from friends who liked serving me organically. Still, I never had a stable.

It's a lot of work. I have stuff to do. I love to play, but outside of that, I'm pretty dull, and I really value my alone time hobbies--like running alone, reading, and cooking. I think I am an independent and capable person who doesn't feel trading my private, alone time for tasks I can almost always do better myself is a good trade-off. Especially when slaves realize it is not as sexy as they had it in their minds and leave.