Spike Dimentos was a long time friend of the Beginner and the Writer. They shared history in the past of which the details are not explicitly known.
At one point the three and the Doctor had encountered in the Writer's TARDIS with business about M-Radiation, but the Doctor forgot this encounter. (The Time Bubble)
After the First Beginner, the Writer and Spike all tried to land in France, 2012 at the same time, they all ended up inside the Writer's TARDIS. they resolved this later and ended up in their respective timelines. (The Time Bubble)
After finding out the Death was to return, Spike and the Writer hired allies such as the Daleks, Silence and the Rock Kind and had them imprison the Second Beginner and Joanna Johnson as if they're captured, they'd be safer from the Death. However rescue attempts took longer than expected and he was there for 100 years and Jo was killed.
They tracked down where Jo's body went and was led to Mardock who revealed their location to be the Conversion Chamber, and there they went.
Encountering the Death, battle commenced in which Spike fought with the Writer hand in hand against the Cybermen with swords. After Jo and Mardock were to kill the Death and in return the chamber would explode, they left having briefly met the Beginner's first and third incarnation.
They then went to a park and spoke briefly to the Beginner before departing on a good note. (Battle of the Beginner)