The Engineer

The Engineer was a companion of the Doctor. He was there, with him, from the beginning. Despite his title, he was actually a bred military man. During the time of the Forth Doctor, he had a romance with Romana's Time Lord companian, having previously had a romance with Sarah Jane Smith. After she left, he had a one-sided romance with Tegan Jovanca, and then Peri. During the events of the Five Doctors, he found himself nearly dead, having been given 24 more regenerations by Rassilon, not counting the immediate one. When infected with the fungus a few weeks later, he regenerated. During the Time War, he regenerated 13 more times. He is currantly on his 32nd regeneration, and has a one-sided romance with Martha Jones.