Kimi to Boku no Uta World's End  

Our Song, 君と僕の歌 world’s end

In a world where everything was lost, we met. An unknown illness wiped out half of humanity within six months. Despite surviving as a teenager, Hazufumi lived alone in this barren land. He refused to pursue significant goals because he knew the anguish that came with losing them. Then, one day, I encountered a peculiar girl being trailed by a hundred cats. Our encounter transformed Hazufumi's heart.