"The Triumph of the Demon King" is an original fan novel adapted from Tachibana's light novel "Date A Live". The story takes place in the sequel to the second part of the anime after rescuing Miku. The demon king reverses Tohka and comes to Tiangong City again. Kurumi and Tohka become sisters? Shido, the task of rescuing Tohka is left to you, go on a date with her and make her shy!