Sakuta has started attending university and meets a girl during a group outing.

Uzuki begins blending into her friend group’s dynamic as her popularity grows.

It’s the day of Sweet Bullet’s performance in an ensemble concert at a venue in Odaiba.

A Miniskirt Santa suddenly appears before Sakuta. She says her name is “Touko Kirishima” and claims to have been handing out Puberty Syndrome to people as gifts. Sakuta sees her eyes lock on Ikumi Akagi, a former middle school classmate who is attending the same university as Sakuta, studying in the nursing program. Curious about Ikumi, Sakuta goes on a group date with female nursing program students that his friend invited him to. There, they discuss a rumor about people’s dreams coming true after they post about them on social media with the hashtag #DREAMING...

A pumpkin lantern made of glass comes crashing down in a plaza in front of Sakuragicho Station, just as a social media post with the hashtag #DREAMING had predicted. However, Ikumi rushes in to protect a girl who was running directly underneath it as it falls, preventing any injuries. She believes the rumor about the #DREAMING posts and has been going around saving people. Ikumi visits Sakuta at the university and passes him an invitation to their middle school reunion. Sakuta warns her about helping people too much, but she ignores this advice...

A poltergeist-like phenomenon attacks Ikumi. Sakuta is worried the attack was caused by Puberty Syndrome, but Ikumi claims that the only way to fix this problem is by forgetting about Sakuta’s existence. Hearing this, Sakuta is stunned and confused. Without giving him the time to compose his thoughts, Ikumi proposes that they have a contest, competing to see if Sakuta will remember “that day” first, or if Ikumi will forget about Sakuta first.

Upon searching the hashtag #DREAMING, numerous posts were found about attending a middle school reunion on November 27th. Ikumi also dreamt about the day of the reunion, but in her dream, she injured someone and was arrested. Sakuta invites Ikumi to visit Minegahara High School, and there, he shares with her the various bizarre things about her that have been bothering him. On the way home, Ikumi suddenly says goodbye to Sakuta as they stand facing each other with the railway tracks in between them…

Sakuta from the other possible realm sends a message through Ikumi that reads, “Find Touko Kirishima, Mai-san is in danger.” After seeing this message, he tries contacting the Miniskirt Santa, who claimed to be Touko Kirishima. A few days later, he receives a call from her saying that she can meet on December 2nd… which also happens to be Mai’s birthday.

Sakuta dreams that on Christmas Eve, when he is meant to have a sleepover date with Mai, he instead goes on a date with a student named Sara Himeji from the cram school where he works. The Sara in question has the same dream as Sakuta and goes on to confess that she has her own Puberty Syndrome. However, she says that she does not want her Puberty Syndrome to be fixed. Sara developed Puberty Syndrome after a heartbreak, and the symptoms of her syndrome ease her anxiety by making her popular with guys, which she has been enjoying. Sakuta warns her that this is a dangerous move. To which she retorts to provoke him, “What should I do so that I can love people. Like you do, Mr. Sakuta?”

Sakuta sees a familiar Miniskirt Santa on a beauty pageant website that his friend Takumi Fukuyama was looking at. However, he notices that her name isn’t listed as Touko Kirishima, but rather as Nene Iwamizawa. As he continues his search for Touko Kirishima, he receives an offer of help from Sara, which he accepts. One of the symptoms of her Puberty Syndrome includes knowing what a person she has collided with is thinking, and that’s how she figured out that Sakuta was looking for Touko Kirishima. Sara suggests reading the Miniskirt Santa’s mind at the venue where she’ll perform her new song live on Christmas Eve.

Sakuta has a dream that Mai reveals herself as the true identity of Touko Kirishima at a music festival held on April 1st. At the same time, several major social media platforms were being flooded with posts containing the hashtag #DREAMING, leading to platform crashes and access errors. As the hashtag #DREAMING causes chaos among the public, Tomoe Koga tells Sakuta that she had a dream that Mai got into an accident, rendering her unconscious during an event where she was collaborating with the police for a public safety awareness.