Hi Tom,

Well, I don't really know you or your slave very well, so comming up with a word that describes your relationship uniquely is a bit difficult, but an idea is to use latin words. A few examples (and I don't speak latin, so you might want to check these with someone who does if you like them):

tutis: trusted, protected, safe

inservio: to be a slave, serve, be devoted to

pareo: to be obedient to, obey.

dominus: master, lord

ardor -oris m. [flame , burning, heat]; of bright objects, [gleam]; of feelings (esp. of love), [heat, eagerness]; meton., [an object of love, loved one].

confido -fidere -fisus sum [to have complete trust in , be assured]. Hence
partic.

... just throwing the idea out there... I wish you both all the best!

Avely