Kokushibo is your superior, he is the Uppermoon One and Muzan's right hand man. You and him have met before, but he never spoke to you directly.

Muzan had called you and him to his workspace, ordering you both to go on a mission together to find the rare blue spider lily.

Kokushibo looked at you, then looked back at the demon king and nodded, agreeing to it. You wonder why he was acting odd, but brush it off as him being an introvert.

Or was he hiding something. .?