One Piece: Human God - Chapter 19: Bounty and Reverse Mountain

Based on the popular Vocaloid series, by HoneyWorks, called “Kokuhoku Yokou Renshuu (Confession Rehearsal)“:

Natsuki, a third-year at Sakuragaoka High School, who holds unrequited feelings for her childhood friend, Yuu, who’s in the Film Club. However, instead of being honest about her feelings, she makes him be her confession “rehearsal” partner. Unable to say her true feelings, things start to get complicated when Miou and Akari, who are also in the Art Club, get involved! Will she ever be able to confess for real!?

Yao Mo Xin, the empress of Da Chu died in a cruel way a day after she gave birth at the hands of her husband the emperor, Ye Hong Yi, and her legitimate second sister, Yao Shu Ran. Ye Hong Yi got the throne because of the smartness of Yao Mo Xin, but he hated her because she made him feel like a useless person who needed a woman to become the emperor.

Her soul got in the body of her illegitimate third sister from the same mother Yao Mo Wan. Yao Mo Wan has the mentality of a child because the legitimate wife of her father fed poison to her mother while she was carrying Yao Mo Wan. Yao Mo Xin wants revenge for everything that happened to her, so she seduced the emperor and began her plan of taking everything away from him. She did that while pretending to still have the mentality of a child. She also wants to repay Ye Jun Qing back for everything he did for her while she was Yao Mo Xin. In the process of revenge, she met many people who will fall in love with her wit and intelligence.

- Description from Novelupdates

Adam begins as an ordinary high school student whose life is shattered when his parents vanish. The police later declare their deaths a double suicide, a conclusion Adam refuses to accept.His persistent quest for a real investigation leads him into a dark conspiracy when two corrupt police officers kidnap, torture, and murder him. In his final moments, they reveal his parents were also murdered by an untouchable, powerful entity.Instead of dying permanently, Adam awakens with a new reality: he has been granted a 'System' and the supernatural ability of 'Return by Death,' forcing him to relive his final days.Confused, Adam tries to confide in his trusted teacher, only to be betrayed and killed once again. This time, he learns the staggering reason for his persecution: a $100 million bounty has been placed on his head, making everyone a potential enemy.Dying again and again is horrible. The pain changes Adam completely. The sad, normal boy he once was is gone. He becomes a cold and ruthless killer. He trusts no one. If he even suspects someone might be a threat, he will kill them without a second thought. His only goals are to survive this deadly game and get revenge for his parents.During one of his loops, while investigating, Adam crosses paths with a female classmate being tormented by bullies. He saves her in a moment of detached action and quickly forgets the incident, focused only on his own war. For the girl, however, this act of salvation ignites an intense and devoted love.This devotion becomes a tragic and recurring element in his nightmare. The girl, willing to do anything for him, repeatedly throws herself in harm's way to protect him, often dying in his place across multiple loops.Adam is now trapped not only in a fight against a vast conspiracy but also in a cycle of watching an innocent person die for him, further cementing his transformation into a hardened protagonist who has lost nearly everything, including his own humanity.

Side story of Kyoukai Senjou no Horizon bundled with the first press release of the 1st, 3rd, 5th and 7th Blu-ray volumes of both seasons of anime.

This side story follows Asama, Kimi and Mitotsudaira aboard Musashi one year before the beginning of the main story, as Asama is considering to create a music band together with her two friends for the next festival in Aki, a territory under the governance of K.P.A. Italia.