Vampires are mythical creatures that turn into ash when exposed to sunlight. Despite their limitations during the day, they have managed to adapt and live comfortably in modern times due to the existence of night shifts. One such vampire is Toraki Yura, who works at a convenience store in Ikebukuro during the night shift and lives in a semi-basement apartment with blackout curtains to avoid sunlight. He leads a peaceful life by following the rules every day. However, his tranquility is disrupted when he saves a blond-haired beauty from a drunkard and discovers that she is Sister Iris, a nun dedicated to hunting vampires. Additionally, his natural enemy unexpectedly becomes an unwanted guest in his apartment. Now, Toraki must navigate the challenges of dealing with these new developments and protecting himself and those around him.