Oh, well if River counts... eh screw it, I'm not conforming to your 5
Rory
Jack
River
Wilf
Donna
Amy
Rose
Astrid
Martha
The girl from "Planet of the Dead"
Mickey
Jackie
That guy the 9th Doctor picked up for a couple of episodes
I'd rank Sarah Jane and K-9, but I feel like not having watched Classic Who, I wouldn't do them justice.
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