A Peace-Loving Vampire Who Has Lived for Tens of Thousands of Years Has Somehow Become the Strongest in the World

—No, no, aren't you mistaken? Alto a vampire who had lived peacefully for about 2000 years, secluded in his own territory. Then one day, an invitation arrived... Lord Alto, the oldest vampire among the Four Heavenly Kings of the Demon Lord's Army; Please participate in the Demon Lord's Army Executive Meeting. Failure to participate will result in purging.