How to deal with a weird associate?

For context, I’m at a very small boutique and only work with 1 associates in this group. He’s a generally nice guy and means well but he’s got a couple tendencies that are annoying the hell out of me.

For starters he over explains the most minor details and rambles endlessly. Something that can be said in a sentence or two turn into a mind numbing lecture. To add insult to injury he tries to be super articulate and formal at all times instead of just speaking in plain english. I’m convinced he just likes to hear himself talk. Would love to know how to him to just spit it out ~professionally~.

He’s also extremely emotionally invested in the deals which turns into really weird and unnecessary small talk. Feels like a high schoolers gossiping but about deal and the drama with the clients and buyers etc. I simply don’t give a shit and don’t want to talk or think about it more than is required. I get banter but it’s just flat out weird and I can’t humor it any longer. How do I make it stop…I want to talk about literally anything else or just not talk. How do I create some professional distance/boundaries.

He also tends to question everything I do. At first I get it but now it’s just condescending. I’ve consistently done good work but the shadow of doubt isn’t going away. This tied with him over explaining is a painful combo. I want to just start sending work to senior directly but I know that’s a bad idea.

Unrelated to me but while I’m ranting it’s super irritating how much he brown-noses the seniors. Like have some self respect. I get you got to play game but relax.