My guess would be the bus... I've drawn him once before, riding a scooter that's a couple sizes too small for him, but I get the feeling said scooter probably didn't last too long, or is old and prone to breaking down frequently.
At any rate, he's either on his way to classes, or whatever part-time job he works at. I've sorta flip-flopped between Taro being in college, or just being a NEET, but either way he's broke and doesn't have reliable transportation of his own.

Perhaps what he's really waiting for is that one good break that will make it so he doesn't have to wait for the bus in a poorer section of town while a storm rolls in just to make ends meet.