Shū is sleeping on couch when everyone is interrogating Yui. After hearing their conversation Shū asks Yui if she was the girl that the guy mentioned on phone. Yui doesn't answers but the other brothers ask Shū if he knows anything about Yui but he teasingly tells them 'maybe'. This makes all of them angry so they asks that if he knows anything he must tell them. Shū then tells them a man called him few days ago and told him to keep Yui safe and try not to kill her but he forgot to tell this to his brothers. So everyone discovers that she is the 'Sacrificial bride'. Later when all the brothers find Yui in the abandoned room, Shū knocks over a picture when the triplets try to suck Yui's blood which diverges their attention. Shū apologizes and tells he accidently knocked it over leaving Yui confused.
Shū is seen in the limosine sitting quietly with Kanato sitting beside him.
During dinner, Shū leaves the table before everyone, saying that this is so bothersome. When Shū leaves, Reiji comments that he is just like a spoiled child and that he won't even bother coming to the annual family dinner. Later when Yui goes to take a bath and check the kiss marks Ayato forcefully gave her, she hears movement coming from the tub and she finds Shū lying in the tub with his clothes on. She calls his name but Shū just responds to tell her to keep her voice down because he is taking a bath. Yui asks why he is still wearing his clothes, so he asks Yui to undress him at which Yui blushes and tells him why would she do that. Shū responds by asking her that she came here in hopes to see him naked. Yui blushes and feels a little embarressed then denies it and tells him that she only came to take a bath. Shū then teasingly asks her if she wants to join him. Yui tells him why would she do that. She then asks him that they are all brothers, but why do they act so differently? Shū then reveals that they all have different mothers, him and Reiji have the same mother, Laito, Kanato and Ayato are triplets from another mother and Subaru has a different mother. Shū then slips inside the tub but Yui grabs his hand to pull him out. Then he has a flashback about his childhood human friend Edgar who died in a fire. After that, he pulls Yui in the bathtub and demands to let him drink her blood but Yui gets confused. Shū comments about her pale skin and notice Ayato's kiss marks, and calls him a possessive freak. Yui tells him that she thought he was different but Shū tells her not to make any mistakes because he is a vampire and he will show her a whole new world and he bites her. After drinking, Shū says that he knows why Yui came to live with them. It's because her blood is of the finest quality. Shū then tells her to think twice before reaching out to him again and never forget it. Later Ayato comes to Shū and challenges him at a game of darts which he first denies but agrees after Reiji calls him a good for nothing. Laito declares the prize will be Yui. Shū wins the game and walks off without claiming his prize until Laito pushes Yui towards him. She bumps into him and Shū stops and tells Yui that to him humans are just prey for him and that she shouldn't dream about messing with him.
Shū appears in Reiji's flashback where he is outside with his mother after Yui asks why Reiji hates him so much.
When Yui is in the past, she notices a young Shū holding a puppy walking to his mother and Reiji. Beatrix gets up and asks Shū what he’s doing there. He shows her a puppy that his friend Edgar gave him. Beatrix ordered Shū to release the dog and told Shū that as the eldest son and therefore, the next head of the family, he needs to learn how to conduct himself at all times. The butler tries to take the puppy away from Shū but he doesn’t want to let go because he says that he promised Edgar that he’d take care of him but finally gives up due to his mother. He then runs away from there crying.
'We hear Shū’s voice from inside the church telling her to be quiet. Yui finds Shū inside reading something. He asks her if she wants something. She apologizes for disturbing him tells him that something has been wrong with her lately and she can hear a voice of a woman who isn’t there and she feels unsteady and she doesn’t feel like herself. He tells her to come to him and he drops what he was reading and lays her down on the bench. He touches her face and she asks what he’s doing and tells him to let her go. But Shū just chuckles while he touches her neck then bites her. He stops momentarily and tells Yui that her blood has changed and that the awakening is at hand. Yui gets confused and he tells her that her blood is different. He uses his thumb and wipes the blood from the fang marks and licks it. He tells her that it’s hot and bursting out now and goes back to bite her. He grabs her hand when she pushes him off. Shū tells her that her neck isn’t the only part of her that’s supplied with blood; fresh, new blood also flows through her wrists. He says that he can tell, even through her skin because it smells good. He tells her not to move and bites her wrists. He stops and tells Yui that her blood is of the finest quality, he’ll give her that much. Shū asks if she is frightened and says that he’s not opposed to the look of fear in her eyes. He pulls her up and bites her right shoulder. He tells her that her blood is more delicious than anyone’s; it slakes his every thirst. Yui tells Shū to stop and he does. He asks if this is the awakening. Then he says that women are terrifying since he’s all worked up in spite of himself and she’s impressive. He’s about to bite her again when Yui asks what he means by the awakening. He tells her that no sacrificial bride has survived to the point of awakening. When she hears ‘sacrificial bride’, she remembers what the brothers had said when she first arrived. She then asks him the real reason why she’s here and if her father has a strong connection to the Sakamaki’s. He gets off the bench and says that “he’ll” answer her questions. She gets confused and Shū says that he knows that “he’s” in there. Shū introduces Yui to ‘Richter’, their uncle. Shū then picks up his music book and leaves. Later on, after 'Cordelia' awakens, all the brothers feel it. Shū is in the library when it happens.
We hear Shū laugh and asks if he’s sure about that. Shū says that Richter is the one putting on a show and Richter asks what he’s trying to say. Shū gets off the couch and says that to Karlheinz, the head of the family, Richter doesn’t even register as a rival.
Shū comments on how for bait, Yui is a lot of trouble. He is then seen staring at Yui's unconscious pale body, stating that she could awaken at any time. When Yui's body reacts, he says that the awakening has probably started. Kanato asks him that if there's no precedent for an ordinary mortal woman to awaken with the power of a vampire, which Shū responds with a yes because no vessel has endured the process. Reiji then comes up with an unfinished remedy that will kill Cordelia once and for all. Shū says that's unusual for him.
In the limousine, Shū tells his brothers to shut up and that they're ruining his music. When the limousine crashes, Shū comments on how this looks like this was no accident. Then when they conclude that the Mukami's are vampires, he says that this might get annoying.
While his brothers are questioning Yui's whereabouts, Shū tells them to just leave her be and that she'll come back eventually.