Max Tresilian
From Tardis Wiki, the free Doctor Who reference
Max was a Human who joined Pilgrim and befriended Suzie Costello.
Biography
Every day, Suzie would reveal to Max, her secret about working at Torchwood 3 and then wipe his memory with Retcon. This eventually drove Max insane and she re-modeled his mind around certain poems. After Suzie shot herself, Max began killing people and was captured in a bar by Torchwood. He was then taken to the Vaults, where Torchwood discovered their name drove him insane. (TW: They Keep Killing Suzie)
It is unknown what happened to Max, but by the time the Vaults were opened by Bilis Manger he was no longer imprisoned. (TW: End of Days)