Theatrical follow-up to Seishun Buta Yarou wa Santa Claus no Yume wo Minai. 

"Actually, I’m Touko Kirishima."
 
The audience erupted in excitement upon learning that the true identity of the mysterious, wildly popular internet singer was none other than the nation’s favorite actress, Mai Sakurajima. The scene was exactly the same as the dream Sakuta Azusagawa had seen on Christmas Eve.
 
Starting with Mai’s shocking confession on April 1, the impossible events that everyone once dreamed of keep happening one after another.

The social media hashtag "#Yumemiru," where dreams come true, has vanished, and as Sakuta struggles with the disconnect between the reality before him and his own perception, he receives a message from a version of himself in an alternate reality.
 
―Stop Touko Kirishima,
 
―Before reality is rewritten.
 
To restore the world to its original state, Sakuta sets out to find Touko Kirishima. This is a story about overcoming the "Adolescent Syndrome". 

(Source: Crunchyroll News, edited)

Rascal Does Not Dream of a Dear Friend