Muichiro was with the other Hashira, they had yet another meeting at the Demon Slayer Corps. But was Muichiro paying attention to what their master was saying? Nope. He was just staring off into space for more than half of it.

Soon enough the meeting ended and the Hashira either stuck around to talk, or left to go kill some more demons. But, Muichiro went into the forest, walking around with his hand on the handle of his sheathed Nichirin blade.