Nemu Manaka (真中 合歓) is one of euphoria's heroines. A second-year at Rokukeikan Academy, she is Keisuke's classmate and considered to be the most beautiful girl in his class. She's always by herself in class and despite being classmates with Keisuke and Kanae, she has hardly interacted with them.
Nemu is a beautiful young woman with stylized ash blonde long hair in a bun with braids, violet eyes, and very pale skin. She carries the grace and balance of a sophisticated noblewoman, and is also rumored to have the blood of a Westerner in her. Her face is also thinner and is considered more worthy than that of a Japanese girl. According to Keisuke, her proportions are perfect.
Nemu is almost always seen wearing her school uniform, which consists of a traditional sailor uniform with black knee-high socks. In the true end, Nemu lets her hair down and is seen wearing a long white dress.
At It is very good first, Nemu is a observant, quick-witted girl who keeps cool even in extreme situations; it is said that she used to be always by herself in class, barely interacting with her classmates. After some scenes, Nemu is shown to be a cruel sadist who tries to make Keisuke unleash his interior demons, taking advantage of the situation. Even though most of her intentions are unknown, Nemu likes to tease Keisuke and the others during their time locked in the white room, being considered somewhat ruthless and detestable. She plays the role of a villain during most part of the game, due to her actions being purposefully hateable - being the perfect contrast of Kanae. She is hated by Keisuke, to the point that he tries to strangle her to death in Kanae's route.
During Kanae's route, it is shown that Nemu is neither cruel or hateable - she's a sweet girl who cares a lot about Keisuke. She only was playing a role in order to make Keisuke hate her enough for he wants to kill her, all that in order to heal save his life after he was seriously hounded when he tried to protect her. Nemu grew up in a facility where she wasn't allowed to go outside and, then, someday, she ran away and ended up meeting Keisuke, a boy of her age. They developed a strong bound and since then, she never stopped thinking about him, even when they were apart Nemu still made reports about her days in the facility - even talking about Kanae, the daughter of Mrs. Hokari, whom she considered "a friend". In fact, Keisuke was the one that permit her to endure the horrible reality she was in because she was doomed to feel absolute pain and sadness until she left all hope in this word. In the end, Kanae wipes Nemu's memories, making her forget about Keisuke and everything else. Her final personality is childlike and innocent.
Nemu first appearence in the game is when Keisuke Takato meets his other classmates and the teacher Natsuki. Unlike everyone else, she seems pretty comfortable with the situation at hand. When Miyako is eliminated, she doesn't react at all, and later caughts Takato admiring Miyako's body. After this, she blackmails him so she doesn't reveal his secret. After sealing their deal with a kiss, Nemu asks Takato to choose Kanae as his "keyhole". Takato can't bring himself to do it, leading to the game's different routes.
As the game proceed, it is revealed that her true timeline story would be: Nemu was born to become the next generation of "Sleeping Beauty" > Being kept and raised in the facility when she was a child > Ran away > Met Keisuke (as a child) and had good memories with him > The two were captured and bring back to the facility > Nemu begged for him to be released in exchange of him getting his memory of her wiped-out > Years later, Nemu, who was under the watch of Kanae and Natsuki, participated in an experiment held by the organization at the school > Coincidently met Keisuke again there > In the attempt of making Nemu lose all hope in the world and become the "Sleeping Beauty", Kanae killed Keisuke > Nemu begged Kanae to save him, leading to a bet with Kanae that if Nemu can make Keisuke hate her enough to kill her, she will save his life > They were brought into the vitural reality, in which the sex game happened > Nemu succeeded > Kanae save him > Nemu tried to convinced him to go into the "Paradise" with her as she had lost all hope in the real world > Keisuke refused and escaped the facility, with a promise that oneday he would come back and save her > Kanae erased Nemu's memory and escaped with her not long after > After 3 years of running and hiding, Nemu, now has a child-like personality, was found by Keisuke > The two happily reunited and ran away together.