A Vermintide/Vampire Isekai. Illust: Doodlin_Noodlin
War is coming to the Vampire Kingdoms. The Rodiens Counts, Ratmen who exile their excess population, need to expand their borders. The Castle of Erztein is preparing for the worst.
Then the Demon Consort, Ynqths Hereid Seraien (everyone just calls her Inks), decides that this would be a great time to Summon someone from another dimension.
She summons half-American "Ash" Satoshi Amaiishi, a 23 year old ex-NEET who has problems getting out of his cynical shell. Through his summoning though, he gets turned into a vampire. Vampires don't kill people, but they do require constant access to those willing to be bitten.
While Ash may be able to get support from the people who love him, War is here. And in War, no one has time for cynics.