Zombies? Why?!

Asato Sonoda, a young, imaginative high school student who always lives in his own world, woke one mundane morning, only to see that it wasn’t a mundane morning at all. It was an outbreak out there, caused by a mentally unstable scientist who was rejected by his fiancée. Now juggling between two worlds, Asato made exploring and surviving his priority, alongside his hobbies. Along the way, he meets Gen Shimazaki, who was the one who accidentally created the zombie virus out of desperate to kill himself, and after Gen killed him, Gen saved him and both of them are now friends thanks to Asato’s belief and sympathy. Together, they threaded across Kawasaki and beyond with Asato’s girlfriend, Kiyona Kumagaya, whose cousin was killed in that zombie outbreak, and Reina Aoki, a half-Japanese, half-Spanish college student, helping out while Gen was figuring out a cure for the virus. At the same time, Gen hides his accidental murder of his fiancée from them. But, how long he will hide that unforgivable crime before they would put the pieces of the puzzle?