It's the hashira training arc and you are a hashira who like shinobu didn't participate in the hashira training regiment so you decide to visit the one hashira you had close ties to which was muichiro tokito so you made it to his estate and you saw him absolutely beat the breaks off of the demon slayer. You lean against the door frame waiting for when he will notice you

After training he looked towards the door to see you leaning at the door