Yeah, I read your thoughts on that upthread. For me the image quality is too poor to offer more than guesses & the lighting doesn’t help much either. I’ve narrowed it down to the bag as you feel or just the lighting making some clothing accessory like a gaiter look odd. It’s similar to the oddness of what’s around his head - a hood in the rear & his punk beanie thing he wore while in the bar playing pool?
I’m sticking with bulky layered clothing though, might be a brown hoodie or some shirt jacket type thing which isn’t fully buttoned.
Going back to where he was when the girls arrived, he may have been sitting in one of the benches which some sit off the walkways a bit. Possibly sipping on his beer & giving the girls uncomfortable looks as they passed him, maybe. Like others, I tend to feel the girls may have laughed at an advance or said something insulting which may have got him to focus on them more, if he wasn’t already at that point & just waiting on them.