From Seven Seas:
When the zombie apocalypse came to Japan, Satou Masaru thought he was a goner for sure…until two super hot girls came to his rescue! But Satou’s relief is short-lived once he realizes just how insane his saviors are: Nakiri Karin is a happy-go-lucky psycho, while Sekigahara Miki is a megalomaniac with plans to create an undead army and rule the world! Can Satou survive being their underling, or will he take his chances with the zombies?!

Original Web Manga