Kono Subarashii Sekai Ni Bakuen O! Vol. 1 (Light Novel)

Kono Subarashii Sekai ni Bakuen o! is a spin-off to the main KonoSuba series. Written by Natsume Akatsuki and illustrated by Kurone Mishima, it's set around a year before the main series and focuses on the previous life of Megumin.
In Vol. 1, Megumin is determined to study exploding magic, but returning home from school one day finds her sister Komekko hugging a strange black cat…
Notice: This light novel is written in Japanese.