I haven't posted a Doctor Who story in a while so here is what I came up with a few months back when presented with the prompt "Till the end of time."
One day he was going to have to stop asking that question.
Each companion, every single one, was asked the same question and they all answered exactly the same, or near enough.
"How long will you stay with me?"
"Forever" "Always" "Till the end of time"
They all made that promise but not one of them kept it.
They all promise but it doesn't last. One by one they all leave. They get tired, they fall in love, they want to settle down, they find their purpose, they discover their place in the universe, they get older…they die…
Whatever the reason, no-one ever stays. Not even Time Lady's or Tin Dogs managed to make it last, no matter how strongly they promised.
Jake answered differently.
This Jake who had a double in a Parallel Universe, this Jake whose double battled Cybermen and Daleks, this Jake who he hadn't meant to run into, just smiled softly and said:
"Until it's time for me to leave."
That, somehow, hurt more than all the unfulfilled promises made by his other companions over the years.
He was definitely going to have to stop asking that question.
The answers hurt far too much.