Oh I like him already. This is exactly the kind of shit I pull all the time, it’s so much fun.
So here’s the deal. You’re not allowed to ask to use it. He knows you want it, and if he’s reading this he knows just how badly, but you’re not allowed to ask, you just have to trust him, and convince him you should be allowed.
This will involve, at the very least, a lot of cock sucking, that’s a given. But maybe there’s something else you know he loves you don’t do much, or at all yet? It might be dressing a certain way, or a habit you want to stop (not being a brat at all is a good baseline) or some sexual thing. Give him that too.
DO NOT use it as a bargain ‘if I do this can I use my vibe?’ no, no, no. You don’t even mention the vibe, that’s the challenge, you do it for him and ask nothing in return.
Then see what happens…