Date A Live Novel Volume 9 was written by Koushi Tachibana and features illustrations by Tsunako.

After a harrowing game of find-the-Natsumi, Shido successfully discovered who she was impersonating. Unfortunately, Natsumi didn't take the loss very well and in a fit of rage, she used her powers to turn everyone into children! Now Shido is up to his eyeballs in crybabies while dangerous trouble brews at DEM. Nothing's ever easy, is it?