Warhammer 40K: My Daily Life as a Commissar in Chaos

[Warhammer 40K + Astra Militarum + Khorne + World Eaters + Space Marines + When the Stars of Mankind Shine] After traveling to Warhammer 40K, I can finally be loyal to the Emperor, but why is my planet on the edge of the Eye of Terror? What do you mean it's right next to the World Eaters' station? What does it mean to be surrounded by Khorne demons? Why are the hives filled with cultists? Overall, this is a "happy" story in which the time-traveler Karius Roman, as a political commissar, leads the Astra Militarum behind enemy lines (actually deep behind enemy lines in Chaos) and fights bloody battles on the planet Erebus, using his unique faith to fight against the darkness.