How to deal with annoying co-worker

So this dude is basically a 46 year old man child and I don't wanna armchair diagnose people, but he's probably on the spectrum.

He'll say a pun or a "funny" phrase, stare at you till you acknowledge it, then when you do, he'll just keep saying it over and over. Even if you don't acknowledge it he'll say it a bunch then switch to a new one.

He's obsessed with making fart noises then pretending it's someone else he'll even do it while we're eating lunch. I've tried the politely asking him to stop he just says "oh you know I'm just joking" then when I tell him its genuinely annoying he goes full kicked puppy and acts super sad for a few hours and gets all woe is me saying stuff like "oh well I guess everyone hates me I'll just shut up forever". Sometimes he even goes full non verbal and literally just tries to communicate by pointing and or writing notes.

It's not like he's an asshole he a genuinely good guy he's good at his job and he's got your back when you need it.

I guess I just have a hard time finding the balance between not being an ass to a guy with zero social skills and losing my sanity because he can't be quiet for 5 minutes.