Can you solve this?

[Hero_Blade004]

It cannot be seen, cannot be felt,
Cannot be heard, cannot be smelt.
It lies behind stars and under hills,
And empty holes it fills.
It comes first and follows after,
Ends life, kills laughter.

Can you solve this riddle? question question  

[The Unknown Mercenary]

nothing =P

if that aint right then darkness =P or dark <.<