Simeji x The Promised Neverland

Simeji x The Promised Neverland was a collaboration between The Promised Neverland and the Japanese input keyboard app Simeji which was held from December 9, 2020 to January 31, 2021. The collaboration included two Simeji original Kisekae designs, as well as an effects function that makes the characters and logo of "The Promised Neverland" appear on the keyboard by entering specific keywords.

If people entered their name on the Simeji website, they could choose ("diagnose") a character to be when escaping from Grace Field House and the results of their escape. In addition, by sharing their "diagnosis" results on Twitter, LINE, or Facebook, they would receive a Simeji original Kisekae design. On the website, a total of seventeen people received special prizes. Seven people received The Promised Neverland anime Limited Edition Volumes 1-3 Blu-rays and ten people received a poster for season 2 of the anime. Simeji also carried out the "Promised Neverland x Simeji Gacha" where people could challenge a gacha and win special prizes once a day for free. People could received an extra gacha challenge each day by sharing the results from their first time on Twitter. Among the prizes, Simeji's original Kisekae design was available.