Tobira no Soto (扉の外, The outside of door) is a light novel published by Dengeki Bunko, written by Dobashi Shinjirō and illustrated by Shiromizakana. It is the author's first novel and is the Gold Prize winner of the 13th Dengeki Novel Prize (together with 世界平和は一家団欒のあとに), that originally titled as もしも人工知能が世界を支配していた場合のシミュレーションケース1 (What if in case artificial intelligence was reigning the world - simulation case 1).
Originally going to a study trip, Chiba Noriyuki, together with his classmates, woken up and find out themselves inside a room that had never seen before. In this chaos, an artificial intelligence called Sofia suddenly appeared and guaranteed them that as long as they obey rules, they can receive protection from Sofia. But suddenly as a hateful feeling come up with Chiba, he rejected Sofia's protection without even listening to those rules, and slowly be isolated by classmates. And the strange life with restraint and protection start from here....