Also known as Dreux, Dugo or Druon, St. Drogo was the child of Flemish nobility. Orphaned in his teens, he disposed of all his property and became a pnitential pilgrim. He travelled to Rome 9 times and he practiced extreme penances.
He worked as a shepherd for 6 years at Sebourg where he was revered for his holiness. According to some witnesses he could bi-locate being observed working in the fields and attending Mass at the same time. I don't know if this 'doing two things at once' is what led to him becoming the patron saint of coffee house keepers or owners but it is nice to have a patron saint of baristas in this day of proliferating coffee bars.
St Drogo developed an unsightly bodily affliction during a pilgrimage and became a hermit at Sebourg for 40 years. As well as baristas he is the patron of orphans, mentally ill people, cattle, shepherds, unattractive people, midwives, and against bodily ills, sickness and broken bones.
Further information on St. Drogo can be found in Lives of the Saints or Saints Index on Catholic Forum