Torvic

From Tardis Wiki, the free Doctor Who reference

Torvic was a Time Lord who bullied the First Doctor and the Master when they were children. The Doctor killed Torvic at the river Lethe after years of abuse to save the Master. To prevent discovery, they burnt the body. (AUDIO: Master)

In the Doctor's diary, he drew Torvic as a monster in the margins of the pages. (PROSE: The Three Paths)