Misako Date has Schizoid Personality Disorder (S.P.D) it's a chronic and pervasive condition characterized by social isolation and feelings of indifference toward other people, people with it tend to avoid social activities and shy away from interaction from others and they also have a limited range of emotional expression. She also has Congenital Insensitivity to Pain and Anhydrosis (C.I.P.A) which basically means Misako can't feel pain, temperature and can't sweat and she has had it since birth. Btw there is slight BakuDeku in here, I just had to I ship it too much not to