You’re the ONE that I want. “You said you’d never known the security of living in one place and time…well I’m giving you that, Susan.”
Pairing: Susan, and David Campbell.
Relationship: Met during the Dalek Invasion of Earth and their friendship quickly deepened to love as they spent a lot of time together when the Doctor was injured.
Pros: Both Susan and David had nothing, and were starting from scratch. They could re-build the Earth together. David gave Susan a home, an identity just as she wanted.
Cons: They hardly knew each other, only in the chaos of a Dalek war. So the Doctor leaving Susan behind was a risk and it would be very traumatic for her to lose such a valuable and loving person as her own grandfather and to be left with a stranger, even if they were in love.
Great Moment: David sneaks up on Susan and waves a fish in her face, they have a little play fight and end up snogging! the Doctor clearly knows he’s interrupted and later tells them to not stop to pick up daisies.
Did it last? Yes indeed. Susan and David married and had a child together called Alex (as told in several audios).