Room 303

Room 303 (ルーム サンマルサン) is a oneshot by Daisuke Ashihara, first published in 2008.

Short Summary
Yukimaru and his friends investigate the White Mansion as they look for their missing friends and run into the strange Room 303.

Characters in Order of Appearance

 * 1) Yukimaru Ichijō
 * 2) Asumi Amakura
 * 3) Takaaki Katagiri
 * 4) Tōichirō Momozono
 * 5) Karin Yuitsuka
 * 6) Demon
 * 7) Sadohara

Trivia

 * The main five characters reappear in World Trigger as members of Katagiri Squad, while the demon woman appears to serve as inspiration for Mira.