weird title

[Beffi]

Ooh so that's what STEP you means Thank-you.

Kanariya
Wikipedia tells us:

It is yellow-green, with brownish streaking on its back.

So it is possibly not a canary, but the lyrics tell us:
The city is alive
The people are restless
The birds that
fly into the night
are already asleep.

The bird associated with night is a crow? Hence why it is black. I'm not sure.... but that's my expanation. We should just ask Ayu.