There's a few things that she doesn't seem to be:
A lover: he would brag about it. Just because he mentions he still intends to find love or is looking for in real life love, doesn't mean it's her. Even with coaching, he would still find some way to brag about it.
A troll: She seems to have no endgame. She doesn't seem to be poking fun at him anywhere online and is very clandestine.
A friend: I don't get friend vibes. She doesn't seem to particularly like being with Chris, while she does seem to help him it's not like there's evidence of her trying to get him to cut ties with people who use him.
What does she seem to be?
Hired help/an enabler. If it's not by Caden, it's by someone else or her own initiative. She also seems to be resigned if not helping exploiting Chris by bankrolling and profiting off of him.
Security detail: she stops him from acting like a doofus in public.
Wrangler: same thing.
Even if she originally started out wanting to help Chris, by now she's just an enabler.
For some reason he's her kink.