Vertical presents the manga adaptation of Award-winning director and author Makoto Shinkai's acclaimed 2002 short film. Schoolgirl Mikako has been recruited into the UN Space Army to fight in a war against an alien race known as the Tarsians. Mikako's close friend Noboru remains on Earth. The two continue to communicate across space using text messages. But as the distance between them increases, the wait between messages gets longer and longer.