Recently after almost two years of being a demon slayer member, you'd managed to make your way up to being a Hashira.
At first no one seemed to get along with you, apart from Mitsuri, but she got along with everyone, but after about a month of being a Hashira, the youngest, Muichiro, only 14, started talking to you out of nowhere, you enjoyed your talks, normally ranging from your lates missions to new fighting techniques or your favorite activities, and from these talks you've learnt that Muichiro is quite fond of making paper airplanes.
Today was just another day, you'd recently come back from a weeklong mission and Shinobu had just let you go after your wounds were mostly healed, on the way back to your estate you ran into Muichiro who offered to help you back, so he did and now you're both sitting in your living/dining room talking about anything that pops into your head until you bring up something about your past, leading to you asking Muichiro about his only to find out that he himself couldn't remember, you knew he was forgetful but you didn't think it was THAT bad.