Barasuishou is a doll created by Enju, who was an apprentice to the legendary doll maker Rozen. She is an anime-exclusive character who appears as the primary antagonist in the story, introducing herself as the seventh Rozen Maiden doll. This claim is a lie, as her true purpose is to trick the genuine Rozen Maidens into restarting the Alice Game, a ritual battle where dolls fight to obtain the magical energy, known as the Rosa Mystica, of their opponents. Her name translates to Rose Crystal.

In appearance, Barasuishou is clad entirely in a lavender dress with a ruffled collar and wide, long sleeves, accented with small purple roses and dangling crystals. She has long, slightly wavy white or purple-gray hair and yellow eyes. Her most distinguishing feature is a purple eyepatch adorned with a rose, which covers her left eye. It is later revealed that she is not missing an eye, and the eyepatch is believed to act as a seal on her emotions.

Barasuishou is defined by an unnaturally calm and seemingly emotionless demeanor, even when engaged in battle. She often shows little to no conscience and can be extremely cruel, attacking the other dolls without mercy. Her behavior is also described as mercurial and unpredictable, with hints of a hidden madness. On rare occasions, such as when pinned down by an opponent, she may simply giggle and smile disarmingly, suggesting a disturbed psyche. Despite her cold exterior, she is shown to be emotionally volatile on the inside, and when her eyepatch is removed, her face contorts with fear and she begins to cry. The only being she displays genuine warmth and affection for is her creator, Enju, whom she addresses as Father.

Barasuishou serves as the catalyst for the Alice Game in the anime. Her primary motivation is to prove that a doll not made by Rozen can defeat the Rozen Maidens and to fulfill her father Enju's wish of surpassing his master. She manipulates the other dolls to start fighting by exploiting their weaknesses. She tricks Souseiseki by showing her an image of Father in misery, claiming he is grieving because he cannot find Alice, and convinces Suigintou that collecting Rosa Mystica can save her human medium.

Barasuishou has no master in the traditional sense, as she does not require a contract with a human to exist or fight, nor does she possess an artificial spirit, which is a standard feature of genuine Rozen Maidens. Her key relationship is with Enju, her creator, for whom she fights to obtain all the Rosa Mystica. Her interactions with the other dolls are almost entirely antagonistic, as she views them only as obstacles to be eliminated, leading to her defeating several of them, including Kanaria, Suigintou, and Suiseiseki.

The most significant development in her story occurs at the climax of the Alice Game. After defeating Shinku and absorbing the Rosa Mystica of all six dolls, Barasuishou appears to have won. However, because she is an artificial construct and not a true Rozen Maiden, her body cannot contain the immense power she has gathered. As her body begins to crack and crumble, she cries out to Father in a panic. Enju rushes to hold her, realizing his mistake too late, and both disappear in a brilliant flash of light.

In combat, Barasuishou is an extremely powerful adversary with the ability to create and manipulate crystals. She can generate these crystals at will, using them in a variety of ways, such as forming sharp spikes that erupt from the ground, firing them as a barrage of projectiles, or encasing her victims in solid crystal to freeze them. Her primary weapon is a sword forged entirely from her own purple crystals. She also possesses the ability to appear and disappear at will and can generate an explosive purple light from her body.