"Mark's father, Sir Mewan Winters"

As Joanna Briscoe points out in this Guardian review of The Lessons, Mark's surname is a single letter away from that of Henry Winter, one of the main characters in Donna Tartt's The Secret History, a novel which has had a clear influence on The Lessons. In both books a less privileged outsider is accepted into a group of affluent and charismatic undergraduates who gather together in a large, impressive yet dilapidated house. Mark's surname seems to be a direct reference to Tartt's book.