Pen was the runt of the litter - smaller, weaker, and less malicious than any other Fetchling he knew. For a dextrous race, he was practically clumsy. The others laughed at him and joked that Pen could manage to trip over his own shadow...
How right they were.
Living in the Plane of Shadow was dangerous. There were all sorts of nasty creatures that lurked in the darkness and culled slow, weak, or inattentive Fetchlings. It was the way it was. Some lived, some died... and some bet on who would be a victor or a victim in that deadly game. Pen, quite reasonably, was on the top of everyone's 'Victim' list.
Year after year, Fetchling elders lost money betting against Pen. For while he wasn't strong or fast, Pen did have an edge or two. He had brains, sharp eyes, a desire to be better than he was, and (most importantly) he had a friend - a very special friend. When he met Umbra as a child, he mistook the shadowy creature as his death. Fetchling children caught alone didn't beat undead. But Umbra didn't feed on him, Umbra wanted to help him. Umbra liked the runty little child and Pen, isolated and teased, was happy to have any friend. So, while other Fetchlings were practicing being sneaky, Pen spent his days playing with his only friend. They became close, closer than close, closer than anything. And the strange shadowy creature told him secrets: secrets about the Plane of Shadow, secrets about itself, secrets about the worlds, and secrets about the gates that existed to other planes.
The biggest secret Umbra shared was as to its nature.
Pen, my friend, I'm a True Shadow, a fragment of this plane itself. For Shadows to exist there must be light and there must be an object to cast that shadow into reality. If you'll be my object then I will always be your Shadow. Where you go, I can go and I'd like to see some other planes...