Insomniac

As he sits in the dark, typing away at his computer, he hears the sound of morning birds chirping away and realizes he has been up all night - but the insomniac still refuses to sleep.

Sami was like an insomniac.

Yanni has been a bit of an insomniac lately.

I am an insomniac.

I'm an insomniac.

I'm a bit of an insomniac.

The insomniac always bows to the absence of sleep.

Tom is an insomniac.