Should've just redirected his hands then smoothly without him noticing.

This is how you know you need to hit the gym up and put down the mickey D's.

At least he didn't try to start sucking your pits.

Well, that's the pits. Since you're just getting to know each other, just inform him of your body so that he can keep abreast of things.

He probably have a thing for armpit and not boobs

That's when you grab his hand and help guide him. Honestly, my arm pits are so ticklish that would never happen.

Ignorance is bliss, OP.

Maybe he was debating on whether he should go for boob or not. I remember as a teen, I really wanted to go for many things, so I would test the waters by rubbing my hands near the areas, but not touching them. Groping armpits is a bit weird in my opinion, but to each his own. I personally would rub my hand beneath the boob on the rib cage until I got a sign that said I was clear for landing. Try making it a little more obvious if it is possible. If he doesn't take the bait, grab his hand and put it there! That typically gets the point across without ruining the mood.

Love your username

Sometimes moving his hand a bit isn't too embarrassing it works and I have never heard a word a guide does work well