Throughout his life, after his rather memorable third year of middle school, Shiota Nagisa had maintained a policy of constant smiles.

Most of them were warm and inviting, of course. Many were disarming, especially when he had to deal with a rowdy student.

This particular method seemed to work equally well on both boys and girls no matter the age.

And then there was the times when he temporarily ceased being a teacher and donned the mask of an assassin. The government wasn't about to waste such incredible talent in the art after all, and when he'd been offered his first job fresh out of high school, it had not taken him long top accept.

Yakuza, corrupt politicians, terrorists, all type of characters that had to disappear into the shadows at all costs before they could cause a ruckus on the very delicate surface of peaceful society. He had gone along with it, still did.

Because deep down, he couldn't let go of the notion that, no matter what he seemingly wanted or how much he admired his former teacher, this was what he was destined to become.

It was so easy, really.

After all, a smile could disarm in more ways than one, and Nagisa knew how to use them.

With the utmost sincerity lacing his lips, he could lower guards, level walls and utterly neutralize self-preservation instincts. A well executed smile and the enemy would suddenly find themselves without a weapon. Another and they would have no space to breathe.

The last thing they all saw was the brilliant, honest smile of the man who had killed them, probably the only sincere one they had had aimed at them in their lives.

The thought made Nagisa feel a little better about it all and he held on to it like a drowning man.

Karma had found out not long ago, though he was careful to keep this fact hidden from most. He kept saying this wasn't healthy for him. That he had his students and that should be enough.

A small part of Nagisa always felt somewhat betrayed at these words.

Could Karma not accept his true nature?

Wasn't he helping?

Wasn't he doing something good?

But instead of protesting, instead of lighting the spark that would set their bond aflame within mere moments, for it had become tragically delicate throughout the years, he smiled.

A smile aimed to disarm.

And so the argument died, as it always did, its life snuffed out with a smile.

Who cared if it wasn't healthy? So what if he was maybe losing himself little by little?

He would just keep smiling. Even as the blood dripped from his fingers. Even as he came back to the classroom covered in lessons and lies.

He kept smiling.