Sankarea: Undying Love

Chihiro Furuya's childhood obsession with zombies has led to his goal of having an undead girlfriend. When his cat Baabu is killed, Chihiro tries to revive him using a resurrection potion. This endeavor brings him into contact with Rea Sanka, a wealthy girl who is unhappy with her life and frequently visits an old well to express her discontent. After a chance meeting, Rea encourages Chihiro to continue working on the potion. With the aid of poisonous hydrangea flowers from her family garden, a potion is successfully created, but Rea mistakenly drinks it, believing it will end her life instead of reviving her deceased cat.