Danny Pink - formerly Rupert - was a teacher at Coal Hill School, where he taught mathematics and established the Coal Hill Cadet Squad.
Biography
Danny, then named Rupert, lived in West Country Children's Home in Gloucestershire for some time when he was young. One night he had a nightmare of someone under the bed grabbing his ankle, and he met the Twelfth Doctor and Clara Oswald. They encountered a figure the Doctor believed to be a creature that hides under the bed. His mind was scrambled by the Doctor to prevent remembrance of this encounter.
Pink joined the army where he performed a number of humanitarian tasks, such as building wells, alongside traditional military work. (TV: Listen) Following his exit from the army, he would become distressed when mention was made of him having killed while a soldier.
Shortly after beginning teaching at Coal Hill School, he was introduced to Clara Oswald by Mr Armitage. She invited him to join her at Kathy's retirement party after work that day, which he initially declined — an act he immediately regretted. While reviewing this awkward moment to himself, Clara overheard him. Although this further embarrassed him, he gratefully accepted her offer to grab a drink together. (TV: Into the Dalek)
The two went for a drink at some point later, with mixed results. The couple argued several times, and Clara left twice, the second time when she was summoned by Orson Pink, who she believed to be The Doctor. Despite these difficulties, the two shared a kiss soon afterwards. (TV: Listen)
Eventually, he would become the great grandfather of Orson Pink. (TV: Listen)