EDIT2: Complete summary now thanks to our awesome translator Kurochan :). Enjoy!
Daiki tells Shiori that they did dirty things together in the past. Shiori calls bluff, but Daiki smirks and says he isn’t. She says he dislikes her so much, but he laughs that emotional and physical aspects can be separated. She is quite upset and exclaims that Akio calls him his closest friend, and because of that, despite her current irritation with him, she is going to bear it and still try to like him as a person for Akio’s sake. Daiki says that it is a cute way of thinking, but his face is a giveaway that he thinks it is illogical. And if it were true, Shiori tells Daiki very seriously, keep it a secret from Akio. Daiki’s phone starts to ring, and it is Akio calling to check that Shiori is with him. When Akio offers to pick up Shiori, Shiori shakes her head vehemently. When asked how they ended up together, Daiki says that she was staggering and crying when he met her on the road, so offered her a lift. Shiori denies the crying having occurred. Sensing how worried Akio is, Daiki placates him by telling him that he is sending Shiori back now and hangs up. Shiori looks down and states that Akio is too good a person, too good a brother who only gets really upset once in a while. 6-7 Well, Daiki tells her, as a sister, she has to give her blessings to Akio, as he predicts that Akio would be getting married.
When they get back to the house, Akio cheerily welcomes them in, but Shiori just trudges back to her room, weakly replying him. Akio is concerned about her attitude, and thanks Daiki for sending her back home. While lying on her bed, she thinks of how Mizuki and Akio are already at that stage, and wonders if they have already done it. This gets her agitated and she tries to stop thinking about it, convincing herself it can’t be, but instead she remembers what she had overheard the last time…
The next morning, when Akio asks whether she wants the jam, Shiori replies she is fine with what she has in a surly manner. When he offers her margarine instead, her reply doesn’t change and she just focuses on eating her plain bread while her two siblings stare at her wondering what happened.
As Mizuki is applying her make up in the room, she asks Akio what the manager said. He was told to try and help with the situation, but Shiori has verbally expressed no desire in modelling, probably overthinking things. He feels that he is the same. He felt Shiori wasa very happy when the magazine was published, and when she was failed to make it, despite feeling down, she put up an expression as if nothing had happened. They leave the room and by the elevator, Mizuki shows her support for Shiori to preserve and enter the modelling industry, and will do all she can to persuade her. Akio doesn’t think there is a need for persuasion, as it should be decided by the person doing it, whether they want to do. He doesn’t want to be particularly unreasonable about it. Mizuki solemnly questions if he understands the consequences of having such an attitude. Akio ponders on his way home why Mizuki was showing such an expression of hurt, and thinks how the atmosphere didn’t fit the discussion about Shiori.
Shiori is waiting at in the hallway when Akio gets back. Her face is solemn as she asks if Akio went on a date with Mizuki. While he confirms it, Shiori grabs his collar and sniffs the inside of his jacket, whiffing a soap smell even though he just returned from outside, hinting that he had slept with Mizuki.
Shiori receives a call from the editor, requesting her to model for their hair and make-up feature. Shiori begins to reject starting with that she doesn’t want to be involved with such stuff, but the editor says she is giving her the job because what she told her previously has been weighing on her mind, even though the audition was really quite bad. She doesn’t give Shiori much chance to reply, telling her date and time, saying she will mail her the venue later and warns that if she doesn’t come, there will be a gaping hole in the magazine spread, then promptly hangs up. Shiori just thinks over the news while standing on the train platform. Zoom out, and turns out it was the manager guy who had asked her to act it, but she does personally hope that Shiori would appear at the shoot, saying that she has taken a liking to her. The manager smiles and tells the editor he is treating her to sushi.
Shiori meets Daiki at the pier, and states outright that she likes Akio, and somehow can’t think of him as an older brother. Daiki wonders why is she telling him this. Shiori feels that he could perceive her feelings. That is why he specially told her how far Akio and Mizuki’s relationship had progressed to. Daiki pauses for a while, then tells Shiori never to tell Akio this. Knowing Akio’s nature, he would pointlessly worry about it. Shiroi of course knows that, and thinks to herself, that is why she is being a good sister to him.
Shiori appears on set, and firmly states “Just this time”. She is primped up, and ready for the camera, looking cute. Even Shiori is surprised at her own transformation. She starts to take the photographs, and is told to smile showing her teeth.
The photo shoot wraps up and Shiori thanks the staff for their efforts. She specially thanks the editor for the fun she had today. As she glances up, she sees Akio there, who wanted to see the set. He is surprised by how pretty it is. 26 Tears well up in Shiori’s eyes, and finally pour out as she tells Akio that she wants to do this job. As Akio hugs her to comfort her, she asks him if it is fine she calls him older brother from now on.
Thinking back to Daiki’s advice, Akio breaks some news to Mizuki: he and Shiori are in no way related by blood, a pair of sibling not bound by blood ties.