Yah it means he is an inconsiderate pervert who needs to learn boundaries and respect.
What does it mean if a guy snapchats you shirtless? Is he just doing it because he doesn't care or is there another reason?
Is he sending it to only you or is he sending it as a "story" to everyone on his Snapchat? If it's only to you, he either likes you or wants you to reciprocate (and DO NOT send him THAT kind of pic back). If it is to everybody, then he is simply an egomaniac, trolling for all the wrong things.
He's likely full of himself
He wants you
His mom's doing the laundry
He's so nice, he gave people the shirts off his back
It most likely means he is an immature, self-absorbed boy. To put it more clearly, don't waste your time.
Who the heck would know with ANY level of certainty what HE is thinking?
He 'could be' thinking "I'm too sexy for my shirt"
He 'could be' thinking .. "dam! My only shirt is in the wash! .. And I gotta snap chat !"
He 'could be' thinking .. "I keep thinking I forgot to do something important when I was getting dressed this morning, and for the life of me, I can't think of what it could be"
He 'could be' thinking wearing a shirt or not wearing a shirt is really not that important to him, and he couldn't give a ratz azz what anyone else thinks
.. Or it could be none of these examples ...
Take your pick.
"Showing off his rib cage."
he's hungry for attention, don't fall for it, you're not the only one who received that from him.