You joined the space marines shortly after you're father died.
You're father was a marine, he had destroyed the demon empire that
threatened to destroy the human race. He had told you many stories
when you were a child, about the imps and zombies, and the arch-viles and the cyberdemons, and how he ran away from a few Barons those moments when health and ammo were low. He dreaded the fact that all those demons he missed might still be down there but he could do nothing, for he was old and weak. When he died, you suggested to set up outposts all around hell to moniter the happenings, but there was nothing. They sent search teams down into the depths of hell to explore, but still nothing.
Until now.
A message was sent to the base from outpost number nine. Something
was spotted moving and doors were heard opening and closing. Some of
the squads were never heard from again. You decided to go check it
out, but not alone...
You and your friend arrive to see no life, but one imp who knows what