You've got a great start here -- I really like the theme of isolation within a crowd. The only issues I can see currently are those of internal consistency. For example:
her boots clicking slightly as they slid across the metallic tiles
How can boots click when they're sliding?
The only noise was the quiet shuffle made by the People on the sidewalks
If they're all wearing uniform clothing, why are her boots the only ones that click?
The elements were the only free ones here, She thought, and even they were imprisoned.
Imprisoned by what? Are they somehow controlled? They seem free enough.
He exhaled again, feeling the cool night air chill his chapped lips
How do you feel the cool night air when you're exhaling? IME, you feel the heated air from your breath when you do that.
He heard a rhythmic tapping coming down the sidewalk, the sound of someone hurrying to get home, carelessly stamping their feet
I thought she was in a crowd of people? Where did they all go?
He had saved her, a complete stranger. Why? It would only bring him trouble.
How can telling someone not to walk into traffic cause trouble? Some things you can get away with just hinting at, like the fact that she "can't afford" to get caught out after the Sleeping Hour. It doesn't matter really whether it's literal or figurative, whether the punishment is a fine or something worse, but where is the crime in warning someone to be careful?
They are also, apparently, on an extremely busy street. Is there no noise from that? It's possible that vehicles in this world are silent, but up until that moment, we get the impression of solitude, lonliness, and emptiness. Then all of a sudden the world is filled with traffic. That's fine if the story were entirely in the woman's point of view -- she's obviously paying no attention to it -- but the man is watching and observing and saw the danger.
I would also advise to guard against using the passive voice too much.
I really like the way you capitalized the nominative pronouns (he, she). I did notice you didn't also capitalize the possessive ones (his, her). That's very interesting, and suggests some cool stuff going on.
no subject
her boots clicking slightly as they slid across the metallic tiles
How can boots click when they're sliding?
The only noise was the quiet shuffle made by the People on the sidewalks
If they're all wearing uniform clothing, why are her boots the only ones that click?
The elements were the only free ones here, She thought, and even they were imprisoned.
Imprisoned by what? Are they somehow controlled? They seem free enough.
He exhaled again, feeling the cool night air chill his chapped lips
How do you feel the cool night air when you're exhaling? IME, you feel the heated air from your breath when you do that.
He heard a rhythmic tapping coming down the sidewalk, the sound of someone hurrying to get home, carelessly stamping their feet
I thought she was in a crowd of people? Where did they all go?
He had saved her, a complete stranger. Why? It would only bring him trouble.
How can telling someone not to walk into traffic cause trouble? Some things you can get away with just hinting at, like the fact that she "can't afford" to get caught out after the Sleeping Hour. It doesn't matter really whether it's literal or figurative, whether the punishment is a fine or something worse, but where is the crime in warning someone to be careful?
They are also, apparently, on an extremely busy street. Is there no noise from that? It's possible that vehicles in this world are silent, but up until that moment, we get the impression of solitude, lonliness, and emptiness. Then all of a sudden the world is filled with traffic. That's fine if the story were entirely in the woman's point of view -- she's obviously paying no attention to it -- but the man is watching and observing and saw the danger.
I would also advise to guard against using the passive voice too much.
I really like the way you capitalized the nominative pronouns (he, she). I did notice you didn't also capitalize the possessive ones (his, her). That's very interesting, and suggests some cool stuff going on.
Hope that helps!