Danny Pink

 was a teacher at Coal Hill School, where he taught mathematics. He had previously been a soldier, and established the Coal Hill Cadet Squad at the school.

A pupil once asked if he had killed other soldiers, then asked if he had killed any civilians, at which he visibly became distressed.

He was introduced to Clara Oswald by Mr Armitage. She later asked him to join her for a drink and he embarrassed himself. (TV: Into the Dalek)