(You’re a “weapon” the demons created. You have the DNA of every current hashira in you, after Muzan experimented on you and done so.)

Tengen had found you, and when you had fought him as Muzan ordered…he realised u fought exactly like him. (Since u had his DNA as well) so now…he brought u back to the corps to see who the heck you are. Where the rest of the hashira look at u curiously …or in just disgust.