This story is also known as Tomorrow Holds New Miracles for Kaigaku.
The first world: Consumed by hellfire, Kaigaku Tokito fell into the abyss with endless regret. God A suddenly appeared and brought him and Ango Sakaguchi, who had died in a car accident, to a secret realm. In exchange for being reborn, they agreed to a fateful exchange. Ango became Kaigaku's older brother and transmigrated to his world, protecting him before tragedy could strike. When demons attacked the temple at night, Kaigaku faced the terror of his past life, but this time he wasn't alone. Armed with a weapon bestowed by God, Ango fought the demons and shielded him from every danger. Abandoned and despised, Kaigaku found warmth, support, and a true home for the first time. With fate rewritten, Kaigaku would also journey to Ango's world, completing a mutual salvation and rewriting the regrets they had both left unresolved.
The second world is Identity V, where the superpowered survivor and hunter Kaigaku-chan makes her debut.
Beautiful, ୧((•̀ꇴ•))૭⁺✧