That's no ordinary dude. He either has some kind of rare medical eye condition or he's a yakuza, based on wearing sunglasses indoors. Or he's an overgrown chuuni.
I have never thought about it before, but could it be Japan has no bigger cats than the house cat? I can't actually remember any from all the manga I've read over the years. Pretty sad for a nation loving cats as much as Japan, if true.