A family of assassins

What if those yellow orbs from korosensei's death was a disease and it caused 10 ppl in Japan to turn into octopus and kill over 10,000 ppl... including karasuma and irina... join there kids Ryuji and Taiga who go undercover back in time to save the world from the octo 10 and bring back there parents! I do not own assassination classroom or it's characters. Inspired by @theinstatesformula THE STORYS ARE SUPER SIMILAR OK IM SORRY I JUST WANTED TO RE-WRITE MY OWN VERSION