(No way is this related to my three main ocs, this is entirely it's own thing that kinda made me realize how much the video above sort of relates to Kanba's story.)

Kanba was sitting in the main room of Team Hanzo's hideaway, kinda just sitting by himself with his Silver Saber in hand, all lost in his thoughts. Thinking of things he's done before arriving here at Hanzo Academy.

???: Kanba...

Kanba jolts a little bit, interrupted from his thoughts as he looks around, finding nobody else with him until a sliding door opens as Asuka comes in.

Asuka: Hey Kanba, I just wanted to inform you that there'll be a sparing session in 30 minutes. Also lunch is ready if you're hungry.

Kanba: Thanks, Asuka. Say, can I ask you something?

Asuka: What is it?

Kanba: Do you wish that... Some times you could just go back? Right some wrongs that you've done?

Asuka: Uh, where is this coming from exactly?

Kanba: ...You know what, never mind. I'm just being paranoid about some things. I don't wanna talk about it.

Asuka: Okay? I'll get out of your hair now, just remember what I said.

Kanba: Got it.

Asuka leaves and closes the sliding door, leaving Kanba alone with his thoughts once again, the world around him fading to black, like it was ceasing to exist until there was nothing but a void. Then...

???: Do you blame yourself?

A black figure with a white outline that had an eerily similar body structure to Kanba, Kanba himself looking at this shadowy figure.

Kanba: *Confused* What?

???: Well it's quite common in this situation for a patient to feel a kind of... Guilt.

Kanba: What situation?

???: ....The Accident.

Kanba looks down at his hands, one covered in blood and the other holding Silver Saber, the blade also covered in blood. He looks to see multiple dead bodies laying before him, all of the innocent people he's killed for the sake of proving his skills, but for the wrong purpose.

Kanba: No... I didn't want to... I didn't mean to hurt anyone... I didn't mean to kill anyone...

Kanba couldn't handle another second of looking at this so he forces himself awake by subconsciously slapping himself in the face, breathing heavy and sweating bullets. Then looking down at his sword and exposing the blade from its scabbard, looking at his reflection in the sheen.

Kanba: It's all my fault.... I didn't know what I had gotten into...

He sighs and puts his weapon down on the table before getting up to leave the room and get some fresh air.

(And that's it ladies and gentlemen, Kanba's own moment of PTSD.)