Momo is a shinigami tasked with conveying human souls to the afterlife. Her appearance contrasts traditional grim reaper depictions through predominantly white elements—her gown, hair, and sickle—evoking purity and serenity. A winged black cat named Daniel accompanies her as a constant companion during missions.

Her responsibilities include appearing before individuals nearing death to ease their mortal fears and offering solace to the bereaved. She intervenes directly in human lives, facilitating final communications and resolving lingering regrets. For instance, she arranged a final conversation between a boy named Kouta and his deceased friend Mai, enabling Mai to request care for an abandoned kitten. She similarly guided a grieving girl named Eko to reconcile with her deceased sister’s spirit, achieving emotional closure.

Momo often employs subtle guidance over direct interference. She interacts with those facing loss or turmoil, such as Mitsuki, whom she led to believe his death was imminent to prompt a life reevaluation, ultimately helping him embrace life. She also assisted Sakura, a girl who attempted suicide, by guiding her to witness the impact of her absence on others, renewing her will to live.

Her methods sometimes involve temporary deceptions or altered perceptions for compassionate outcomes. She and Daniel once assumed the forms of a young boy and girl to lead Kantarō to a treasure left by his deceased grandfather, forging a connection to his memory. In another instance, she temporarily babysat a young boy named Fuyuki at his deceased mother’s request, later enabling his sister Chiaki to converse with their mother’s spirit. This allowed Chiaki to learn her mother’s French toast recipe, symbolizing the transfer of familial love.

Emotional sensitivity defines Momo, and she often cries when witnessing poignant human moments, reflecting deep empathy. Her demeanor remains consistently gentle and reassuring during interactions with the dying and grieving.