For those who have just started watching Doctor Who, I recommend not reading this, or waiting on reading this, since I will be referencing future episodes and plotlines. Therefore, to give you a warning and for River’s sake, “Spoilers!”
Practically every single companion that the Doctor has had since the show began was a woman. If there was a male on the TARDIS, they typically were with the female companion. Though we would like to think that the Doctor’s initial plan isn’t to find a romance between himself and his companions, it doesn’t stop the romance from forming.
Since I have only watched a few episodes of the Classic Who, I’ll start with what I do know well, which is the New Who. Rose is one of the first companions that I believe had a large romantic interest with the Doctor. She was with him as both the 9th and 10th Doctor, until she was separated from him. Eventually, she managed to get reunited with the Doctor. At least, she was reunited with a part of him.
Obviously we shouldn’t ignore the Doctor’s romance with River Song, since he did get married to her. However, the story of that romance is far too long and to complicated to even begin in this short post.
In addition, questions on the Doctor’s romance with his prior companions are even asked by some of the current companions themselves. Amy Pond and the 11th Doctor, Matt Smith, have a small and funny moment where Amy questions why the Doctor’s companions are mostly female and what his true intentions are with his companions:
The Doctor’s romance doesn’t even begin nor end with his companions. Through out an assortment of episodes, the Doctor is receiving and giving kisses by a wide range of people he runs into, including Rory in the episode “Dinosaurs on a Space Ship”.
After describing and thinking about these few romantic examples that I’ve posted, it’s gotten me to think that why has the Doctor had mostly female companions? Did the writers intentionally make so that if the Doctor was always male, the companions should be female? Of course, then that brings up the question that if the Doctor became female, would the next companion then be male?