The Light (The Twilight Streets)

The Light were a group of entities who were allied with Abaddon in the fight against the Dark and Pwccm.

Powers and abilities
The Light were halogen lifeforms, seemingly made of bright light. Though not native to them, they could live in temporal rifts. They were capable of taking over people's minds, allowing them to control their bodies. While possessed, the Light could show potential futures. When possessed, their eyes would shine brightly. (PROSE: The Twilight Streets)

History
The Light and Abaddon were enemies of the Dark and Pwccm. They had fought throughout time and space until they reached the Cardiff Rift. They were trapped within until 1876, when the Rift opened in Tretarri, allowing the demons to fight. Abaddon pretended to be defeated, allowing Pwccm to take control of the Rift.

When Jack Harkness killed Abaddon, the Light were forced to fight the Dark and Pwccm alone. They started to lose and Bilis Manger was forced to try to save them, sealing them in a special diary and within members of Torchwood Three to keep them alive. He planned to open the Rift and allow the Light to enter, making them keep Pwccm sealed away for all eternity. At the same time, he would seal the Dark inside a special box, meaning Pwccm would have no help. With the help of Torchwood, he was able to do so. (PROSE: The Twilight Streets)