Raise Unicorn no Kubisuji Ushiro no Hokuro ni Naritai

It's the day before the last performance by THE PARADISE. Three fans who have never met get trapped in an elevator. They talk about their favorite band member, Unicorn, while they wait to be rescued. For some reason, the air is tense. Then, a notification goes off on their phones.

(Source: Geidai Animation)