Geoffrin (The Art of Death)
Geoffrin was a rich kid.
Timeline 1
He visited the Horizon Gallery with several other rich kids and wasn't interested in anything but the Paradox. Geoffrin was bored when Penelope showed him around. He talked with his friends on the telephone and ate during the tour. He treated Penelope disrespectfully. When another rich kid droped a sandwitch on the floor he told Penelope to pick it up. However Amy Pond told Penople not to pick it up and Penelope did not do this. After this Geoffrin and the other kids were attacked by a creature. He was killed by the creature.
When Penelope later realised that her older self was the creature and the paradox, she stoped herself from becoming that creature by sacrifying herself. (AUDIO: The Art of Death)
Timeline 2
As the Paradox did not existed, Geoffrin wasn't killed by it. (AUDIO: The Art of Death)