[He frowns. There is something oddly vulnerable in his confusion, as if he genuinely doesn't understand the question— or, at least, the reason why anyone might need to ask it.]

I spend myself on what I need. What I want. What interests me. Anything else is a waste.

[Which... implies something about the amount of time Kylo seems willing to spend indulging Kavinsky, really, doesn't it? Not that Kylo seems to realise what he's said.]

I have no use for money. And even less for studying it.