Chapter 1: My Homeroom Teacher is an Octopus?!

A story about one grand assassination to a certain yellow octopus being that will destroy Earth on next March.
The world fate has depend on Kunugigaoka's class 3E students, what will they do?
This turn of event bring them many others new things, especially for a certain red haired boy and blue haired girl
(Karma x Fem! Nagisa) (Cover not mine)
cross-published on ffn too