Little Snake Nagisa (Assassination Classroom fan fiction)

This is an Assassination Classroom fan fiction.
If you're not up to date with the manga you may be spoiled!
Nagisa and everyone thought his problems with his mother had been sought out and their relationship was going for the better.

Who knew it was actually going for the worse?

What was Nagisa's mom work anyways? What's this research facility she's working at? Is Nagisa hiding something from them all?

Read to find out.