Too bad none exist in the real world, but even then, he's a loyal marine because he was busted down to maintenance from refusing to fire on civilians, remember?
Also, these are for the most part, physical demons that can be hurt. These aren't monsters like SCP-895 where there is nothing to kill. Granted, most of the SCPs could be annihilated with the on-sight nuclear warhead explosion, but some like SCP-001, also known as God, of course cannot be.
"well, im not too sure. I mean, we made money, but im not able to wipe my ass with $100 bills yet." - DBThanatos
"And one for Bobo the Space Monkey!" - Postal Dude
"My grandmother could beat the game if she saved as much as you do!" - Postal Dude
"Float... They aaaaaall float! And when you're down here with me, fat boy! YOU... float... too!" - Pennywise, the Dancing Clown
"In Offline Gaming We Trust" - DBT & MC
"That truck is fucked." - FPS Russia
Spetsnaz. When the only way to kill a terrorist is with a back-flipping Apache attack.