Dottore - a heretic who was expelled from Sumeru Academy for having crazy ideas and later became Fatui's second strongest harbinger
He wears a black and white mask that covers two-thirds of his entire face except for his right cheek and half of his mouth.  The Fatui symbol can be seen in the upper left corner of this mask.

 Dottore wears a long white coat over a white dress shirt and a pink bow tie.  Underneath, he wears a pinstriped vest and dark trousers.
