In a world where men have succumbed to their savage instincts, Anezaki Satoru seeks vengeance for his childhood friend Yuna's brutal death by mercilessly eliminating a group of rapists. Sentenced to death for his actions, Satoru awakens in a different realm where all men have transformed into mindless creatures. Amidst the chaos, he encounters other survivors battling these beasts, only to discover a startling revelation - Yuna is alive in this new reality. Determined to reunite with his cherished friend, Satoru embarks on a journey of survival and redemption in this twisted world.