The Zaregoto novels, where the character Kishishiki Zerozaki originally appeared, are getting an OVA series adapting the first novel.
Zerozaki Kishishiki no Ningen Knock adapts the similarly titled second novel of NisiOisin’s Ningen light novel series, itself a spinoff of his Zaregoto light novel series.
The story centers on the titular Kishishiki Zerozaki, a member of the Zerozaki family, one of the “Koroshina” assassin families.
The manga centers on a student who finds himself in Manchuria on the eve of the Russo-Japanese War.