Hikaru ga Shinda Natsu

Yoshiki and Hikaru have been inseparable since childhood, growing up together in a quiet rural village. But everything changes when Hikaru mysteriously disappears in the mountains and returns a week later, seemingly unharmed. At first, everything seems normal, but Yoshiki soon realizes that the boy standing before him isn't really his best friend anymore. Something else has taken Hikaru's place, wearing his face and carrying his memories.

Despite knowing the truth, Yoshiki can't bring himself to walk away. He chooses to stay by his side, pretending that nothing has changed. But as strange and terrifying events begin to unfold throughout the village, Yoshiki finds himself caught between grief, fear, and his growing attachment to the thing that looks just like Hikaru.