Despite Kyouko Honda's tragic death, her vivid memory lives on, providing guidance through times of hardship to her close ones. However, Kyouko was not always the wise and radiant person that she is fondly remembered as in the present day. Feeling deserted by her own family and rejected by society, a young Kyouko abandons stability for a life of delinquency, jeopardizing her education and future. Fortunately, her descent into despair is interrupted by a fateful encounter with her husband-to-be Katsuya, who has recently started his teaching internship at her school. With a composure surprisingly unaffected by Kyouko's tantrums, Katsuya quickly wins her over through his gentleness and attention toward her—sincere gestures that she has never received before. As the two grow closer together, Kyouko opens her tormented heart to him and, along with it, a door to new horizons.

Crime-ridden Ikebukuro is a haven for violent gangs, the Yakuza, and home to Makoto Majima. To protect his friends, this charismatic troubleshooter mediates disputes among the warring factions—even fixing problems the police can't. But when a rising tide of violence results in Makoto losing a loved one, can he ride out the storm, or will he drown in all the spilled blood that floods his streets? (Source: Funimation)

Continuing their perilous descent down the Abyss, Riko, Regu, and newfound friend Nanachi reach the Abyss' fifth layer, The Sea of Corpses. Upon arriving at the research station known as Idofront, the main trio encounter the mysterious Prushka, the alleged daughter of Bondrewd, who leads them to the White Whistle responsible for Nanachi's dark past. Despite the welcoming appearances of Idofront's residents, Nanachi warns the young adventurers that things are not always what they seem. With the only route to the sixth layer shrouded in mystery and Bonedrewd's schemes awaiting them, what sacrifices must be made in order to continue the journey down to the bottom of the Abyss? [Written by MAL Rewrite]

Akane Nishimura's quiet nature makes her classmates perceive her as a gloomy and unlikeable person. Combined with her intimidating gaze, it earns Akane the ominous nickname "Grim Reaper," condemning her to endless bullying for her supposed cursed powers that bring misfortune to everyone around her. However, none of these rumors deter transfer student Taiyou Takada from trying to befriend Akane. As someone who finds the supernatural fascinating, Taiyou approaches the Grim Reaper without hesitation, blissfully unaware of the complicated situation within the class. His bright personality and optimistic worldview may just bring about the change that Akane desperately needs.