Kokoro Connect Episode 12

is the twelfth episode of the anime series.

Synopsis
The episode begins with the Cultural Society's greatest fear being realized: Iori has been reverted to an infant. As the gang squabbles over how to take care of a baby, Taichi asks if anyone has milk, which Inaba takes the wrong way. Making their way through a park to get supplies for the baby Iori, Inaba contemplates how this phenomenon is unlike the others considering how Taichi has so far been unaffected and Heartseed has yet to appear. The group is met by  Anzu and  Mihashi, the latter being in a confrontational mood. Inaba decides to flee with the infant Iori and preteen Aoki before anyone gets too suspicious, leaving Yui and Taichi to deal with the situation.

After Yui sends Anzu away for asking too many questions, Yui is confronted by Mihashi who berates her for quitting karate and doing nothing with her life. As she tries to defend herself, Mihashi once again brings up the promise Yui made with her in the past, but Yui insists she remembers no such promise. Done talking, Mihashi challenges Yui to a fight which she accepts, charging at her former rival, fists clenched.

Later, back at the abandoned building, Taichi informs the others that Yui was soundly defeated but Mihashi decided to leave them alone for the time being. Child Aoki tries to cheer up Yui, offering to play games with her but still calling her "Nana's older sister." Yui snaps at Aoki, sick of him mistaking her for Nana's sister, though she quickly apologizes.

That night, Aoki goes to a diner with Taichi and groans about how he keeps associating Yui with Nana. Aoki insists he loves Yui, but can't stop thinking about Nana either. Taichi advices Aoki not to let it worry him too much.

After New Years passes, it has become clear that the phenomenon isn't going to end anytime soon. This time, both Yui and Inaba revert a year younger. Yui freaks out, having been reverted to a time not long after she was almost raped. Younger Yui spends most of the day moping in a corner, which the less-than-compassionate Inaba coldly bashes her for. Despite seeing a different side of Inaba, Taichi mentions that this doesn't change his opinion of her, which Iori applauds him for.

When 5pm passes, the two return to their proper ages, but Yui is still shell-shocked, having been freshly reminded of her trauma. Iori does her best to comfort her friend and Taichi and Aoki escort Yui home. Waiting for them along the way is a more civil Mihashi, who more courteously asks why Yui can't remember their promise. Yui is in no mood to talk and brushes her aside. Aoki implores Yui to give her old friend a chance, but Yui turns on him and accuses Aoki of only liking her because she resembles his past love. Offended by Yui's words, Aoki angrily tells her off, accusing her of once again making excuses so she can keep running away from her problems instead of solving them and that she has no right to criticize him. Realizing his harsh tone, Aoki leaves, ashamed, while Yui falls silent, left hurt by his words. Taichi and Yui talk together at the same park they spoke at before. Yui reveals she finally remembers the promise she made to Mihashi: to one day fight her in the finals of the national tournament. However, after her trauma, Yui gave up her ambitions and lost her purpose, likening her current self to a background character. To describe her situation, Yui pretends to state that she loves Taichi. Yui wonders if someone made a promise with a friend, but the friend never came through on the promise, would the promise maker's feelings change? The metaphor reminds Taichi of Inaba, whom he still hasn't settled his feelings with. Yui goes on, stating that she was once strong, but now she has to rely on others for strength and can't do anything in return, but accepts her fate regardless. Afterwards, Yui takes her leave, while Taichi sadly can only watch as he realizes there's nothing he can do to help her.

Iori, Taichi and Inaba meet Aoki at a diner, wanting to help Aoki sort out his thoughts with everything that's happened. As Iori and Inaba bicker over Taichi, Aoki realizes (on his own) that his problem is that he forgot to live carefreely. Aoki then declares that he's going to find Nana, and he won't be at peace until he does, with Taichi joining him.

On their way to Nana's, Aoki reveals to Taichi that he decided to live carefree after a girl during his 2nd year of junior high died in a car accident. The incident deeply impacted Aoki and made him realize just how fragile life is. As a result, Aoki swore to live life to the fullest so that when he meets his end, he will have no regrets. Aoki, with Taichi in tow, eventually tracks down Nana, and the two exchange pleasantries. Snow gently falling around them, Aoki confesses that while he loves Nana, he now loves someone even more. A smiling Nana acknowledges, and asks the two if they would like to chat more, but Aoki declines, stating that they have a return bus to catch. Aoki and Nana say their goodbyes and, without looking back, Aoki marches onward.

Aoki and Taichi sprint back to the building where Aoki states he has something he needs to tell Yui that cannot wait. When they arrive, they find Yui waiting and Aoki confesses to her that while he loved Nana, he loves Yui now and that his feelings are the same and her resembles to Nana is irrelevant. Yui wonders if she deserves Aoki's love, but Aoki assures her there is no one more worthy. Yui then breaks down, asserts that she is done being helpless and admits she is afraid of men, but she could've admitted that from the start and not forced herself to forget, admitting that her worthlessness is her own fault, not her trauma's and recalls Aoki's words that she was giving up and making excuses and shouldn't care if she wins or loses and her worth is something she has to earn back and resolves to stop being a background character. Yui thanks Aoki for his encouraging words and declares that she will, from her side, take her first step towards overcoming her androphobia. With that said, Yui lunges at Aoki, embracing him tightly. Her androphobia makes her tremble, but, refusing to run away, she only tightens her grip more and more until... she stops shaking. With her androphobia gone, Yui releases Aoki, who asks if she's ok and Yui is shocked by this, that all she had to do was try and proudly declares that she has won this battle over her androphobia, and that from now on, she will never lose again.

Yui's celebration is cut short when Aoki reverts to a child, 12pm having come around. Yui promises Aoki that she will make sure he never again mistakes her for Nana's sister. To her surprise, child Aoki is fully aware who Yui is and Inaba wonders if memories can surpass the power of the phenomenon. Inaba starts worrying how much longer the phenomenon will last but Taichi assures her it won't last much longer. Suddenly, Inaba becomes suspicious of why Taichi knows so much and begins interrogating him.

Trivia

 * Yui describes herself with the Buddhist saying, "Tenjō tenge yuiga dokuson" which roughly translates to "Between Heaven and Earth, I am the worthiest." Inaba points out that this saying is actually not much of a compliment. In Buddhism, all people are considered equal, so really, this saying mostly means "Everyone is unique, so I am not special."