Mea Kurosaki is a second-generation transforming weapon and the younger sister of Golden Darkness, also known as Yami, created by the same organization under Project Eve. She is sent to Earth with the mission of bringing back the "old" Yami, the cold-hearted assassin, but her arrival marks the beginning of a personal journey that challenges her identity. Mea has a laid-back, mischievous, and often childish personality, rarely seen without a smile even during combat, and she enjoys teasing others, particularly Rito Yuuki and the girls who have feelings for him. Despite her playful and friendly demeanor, she harbors a deep internal conflict; she was raised with the belief that she is nothing more than a living weapon, and her earliest memories are of waking up in the rubble of a destroyed research station and meeting Nemesis, another weapon who reinforced that mindset. This makes her initially confused by her sister’s choice to live a peaceful life on Earth, and she longs for Yami to embrace her own weaponized nature. Over time, however, Mea’s experiences on Earth begin to change her. She is first discovered alone and staring out a window, but soon befriends Nana Astar Deviluke, who becomes her first genuine friend and a catalyst for her emotional growth. As she integrates into life at Sainan High, she starts to question her programming and develops real attachments, especially toward Rito, for whom she harbors genuine romantic feelings that she often masks as jokes. Oshizu, after possessing Mea, discovers a profound darkness within her mind that nearly consumes her, hinting at a volatile psychological state. Mea’s abilities are more advanced than Yami’s, as she is a next-generation weapon. She can transform parts of her body into powerful energy weapons, uses her extremely long pink hair as a transformation medium, and possesses the unique power to enter the dreams of others—a technique called Psycho-Dive—allowing her to extract information or influence thoughts. Her signature catchphrase is "wonderful," often uttered when something perverse or unexpected occurs. Through her relationships with Yami, Rito, and Nana, and her gradual shift from a weapon on a mission to a conflicted individual seeking belonging, Mea’s character arc explores themes of identity, companionship, and the struggle between one’s nature and choices.