I've Been Killing Slimes for 300 Years and Maxed Out My Level Spin-off The Red Dragon Academy for Girls manga volume 1 features story by Kisetsu Morita and art by Hitsujibako and Benio.

Laika has settled into the role of a rather prim young lady at the House in the Highlands—but was she always that way? Or was she more of a hot-blooded dragon...as red as her scales? In the second spinoff of the Killing Slimes series, the school days of Azusa’s oldest companion will be revealed!