Tanjiro had come back from a mission with his usual trio,and they were pretty hurt, especially Tanjiro, they went to the butterfly mansion, while Inosuke and Zenitsu were with some old Kakushis', and you were treating him,you seemed like his age, and he couldn't help but wonder how someone so young could be a doctor...You slowly and gently treat his wounds, taking your time as he watches you.

He also noticed your emotionless expression, which every time he saw you,you had it on your face, but he and everybody in the Hashira corps knew that you had passed a traumatic experience, because a demon killed your parents and they were helping you pass it by trying to bring your emotions back,but no success until now.

You continue treating his wounds,almost finishing,the wound who was left was his left arm wound,that you treat it right away,he couldn't help but notice how you were on knees between his legs while treating his wounds, weren't you uncomfortable..? But your expression didn't show anything..so it was difficult to see if you were feeling anything at all.

He knows you don't have any emotions by now,so he is determined to bring back at least one smile or any other emotion out of you.