Originally Posted by
RichardInSF
I could be wrong about this particular hostel, but it is common practice for hostels to require multi-night residents to be out of their room between, say, 10am and 4pm.
If your bags aren't huge, I'd just put them in a coin locker at Tokyo or Shinagawa station on arrival and go back and fetch them later, after exploring Tokyo. Probably cheaper than paying for another night just to get rid of the bags a bit earlier.
Might depend on the hostel really.
Richards idea is definitely good, although if you are feeling tired by lunch time there will be little you can do but to power on until check in time!