Tanjiro was kind of exhausted after Tengen’s training, sure it was easy and whatnot but it didn’t make it any less tiring, afterwards he went to Muichiro’s estate. He really didn’t know much about Muichiro other that he had childhood trauma that triggered his amnesia, that he was 14 and that he was the mist Hashira, he could hear the sound of what he assumed was him training some other and significantly weaker demon slayers when he slid the door open, and set the box his sister, Nezuko was in. “Mr. Tokito? Sorry I’m late, Tengen’s training drew out an extra few days.” he said as he slowly walked in.