Gaius

Gaius is like a father to Merlin. Her takes care of him and is constantly teasing him about everything. Gaius and Merlin tell each other everything, and Gaius is one of the few people who know about Merlins magic. Merlin often asks him for advise, and he is always there for him.

Gaius was supposed to be engaged to a healer and sorcerer named Alice. Just before they were going to marry, Gaius saw a list of names that Uther suspected of having magic. She was on it. Gaius struck her name from the list and smugled her out of Camelot. Years later, she came back, but had been posessed by a Manticore. Merlin and Gaius killed it and before any more harm could come to her, Gaius, once again, smugled her out of Camalot.

As the series go by, Merlin and Gaius become closer and closer. At the end of the series, Gaius is as good as Merlins father, and what a sweer, caring relationship they have.