The sole surviving human and her canine companion, Haru, wander a desolate wasteland after the destruction of civilization, but this is no dark doomsday tale. Haru, a wise-beyond-his-years talking shiba inu, makes sure his master stays one step ahead of post-apocalyptic pessimism with his clever antics, hilarious observations and philosophical ponderings. She may be the last girl on earth, but with Haru at her side, the road through the apocalypse will never be boring!

Fuuta-kun has never owned a cat before, but his younger sister, Pii-chan, moves into his house with the round gray cat Kyuruga. Inexperienced with cats, Fuuta-kun has no idea what to expect, and each night after he returns home is marked by odd and endearing surprises from his new pet.

The Second Europa War is being fought between Gallia and the East Europan Imperial Alliance, and a penal military unit known as the Nameless is on the run from both superpowers. Deemed rebels by Gallia and also a priority target of the Empire, the Nameless struggle to find their place in the raging war. To make matters worse, the company's tank driver, Gusurg, abandons them to fight for the Empire. After liberating a small town from the Empire, the Nameless come across Isara Welkin, an injured tank driver from Gallia's Squad 7. Isara explains to the Nameless' leader, Kurt Irving, that her squad is retreating from a failed raid and pleads for the Nameless to save them. They now face a difficult decision: remain in hiding, or redeem themselves only to aid the nation that marked them as traitors.