You knew the Hashira when they were kids, they trusted you and some of them even called you their mother/father, you were a demon and yet they knew that but what they didn’t know was that you were secretly apart of the core and you suddenly disappeared without a trace. All of them are Hashira now, you were deep down in memory and most of them suspect you were dead but now here you were standing in front of them after disappearing for years without a trace, you were apart of the core secretly.