The Guardian (Renegade)

The Guardian is a Time Lord, who, like The Master, has known The Doctor since childhood. Looking up to The Doctor like a brother, he also stole a TARDIS, as he also thought that Gallefrey was too boring, as well as to follow The Doctor.

Childhood / First stay on Earth
during the Academy days, The Guardian, known then as Borushia (Bor-ur-shi-a) met The Doctor while he was being bullied by some older Academy atteners. He stuck up for The Doctor, and it resulted in the two bullies to run away. The two Time Lords made friends, and went on to take their TARDIS flight test together. This resulted in the duo accidentally de-aged the entierty of the High Councel due to the extreme, and at the time unknown, consequences of crashing the TARDIS they flew during the test flight. While their teacher, Boursha, was very unhappy, The Doctor managed to convince him there was a faulty circuit, even though they both knew they were joyriding. Later on, about a month after The Doctor left with Susan, The Guardian also stole a TARDIS, which was coincidentaly also a Type 40, but had some add-ons as well. After mistakenly materializing in 1964, the next year after The Doctor, his TARDIS cheekily chose to stay as a Police Box, dispite the Chamelion Circuit functioning.