At that time, he had a visible dark aura... but apparently no one else could see him...

Even though he was carrying a weapon out in the street...

Huh? Sensei, that blade you're holding...

It was discovered in a well this morning, together with his dead body.

Akyuu and I have been dealing with the aftermath all day.

No one's seen him in the past few days.

B-But I'm sure I saw him at the bridge today!

It appears he'd been ill for a while now and suffering from hallucinations. He had no external wounds, so it's likely that he fell into the well himself.

Tatsuho, I mean.