Z just got off work. Z did not get enough sleep last night. Z's three consecutive energy drinks are really wearing off.
He decides halfway to the subway no way he can get on the train and get off again at the right place and not the end of the line when somebody nudges him awake, so he sits down on the steps in front of the library and leans back against a pillar to try to call a rideshare or something.
He can rest his eyes for just a second before he actually calls the thing, though.
Or...just a minute.