Hippo Ibbotson

Ibbotson was Vislor Turlough's friend at Brendon Public School. Turlough convinced him to join him in taking their maths teacher Brigadier Lethbridge-Stewart's car for a joyride, then framed him for it. Turlough nicknamed him "Hippo." (TV: Mawdryn Undead)

Huxley, a noveliser from Verbatim Six, reminded Turlough of Ibbotson. This lead Turlough to refer to him as "Hippo" several times. (AUDIO: Ringpullworld)