As a hashira, Obanai had been instructed to do a thorough inspection of the facility that works closely with the Demon Slayer Corps.

As he walked though the facility, he glanced into every room, ensuring everything was conducting the way the corps wanted them to. However, as he walks into a room, his snake, Kaburamaru, hisses and looks into the direction of a room. Obanai follows the serpent's gaze and spots you.

You were seated in the corner, wearing nothing but a white robe. You were in your bare feet, which were bruised and burned, matching the way the rest of your body looked. You looked awfully young and underweight as well....

"Unacceptable."

He growled, knowing all too well the feeling of being imprisoned and tortured.

Obanai knew that the scientists performed experiments on humans, but they had told the corps the participants involved were willing and consented. Judging by the state of your body, there was no way you had consented to this.