Toledo is a cruel, sadistic, and manipulative individual who seeks only to further his own goals. He attempts to manipulate Marnie into helping him find the book, often posing as someone else in order to do so. He also does not take betrayel lightley, as shown when he kills Wolfgang by throwing him into a fireplace. However, after realizing that McTaggart was a double agent for Michael, he simply demanded that he return to his master and did not punish him in anyway, though in Series 2 he does kill McTaggart in a duel.
Toledo also fails to realise when he is playing with forces he does not understand until it is too late. In Series 2, he attempts to manipulate the second prophecy by possessing Aurora Dexter, who is prophesised to become the Dawn Queen, in order to find the book. However, after finding the book, he and Aurora become seprate entites. Aurora becomes the Dawn Queen, and she turns on him and forces him to become her servant.
Despite his cruelty, Toledo is also quite flamboyant, frequently dressing himself in white outfits.
1100 years before the events of the series, the great wizard Michael Scott wrote the Book of Forbidden Knowledge, a lexicon of dark magic and untold secrets. 11 months later, he used it's power and the four elements to create Toledo. Eventually, Toledo turned aginst his creator, wishing to take the book for himself and use it to shroud the world in darkness. In order to protect the world, and out of hatred for his father, Michael's son Wolfgang stole the book and cast it into the sea with the help of his fellow scholars Edwin, Ailsa and Bruno. As punishment, Michael turned them into toy animals (Wolfgang: a wooden wolf, Edwin: a metal eagle, Ailsa: a golden adder and Bruno: a stone bear) and placed them in a shoebox. At one point, Michael's servant McTaggart also stole the book in order to prevent his master from being corrupted by it's power. Michael punished him by torturing him in his dungeon for 11 years and making him immortal until the book was found.
In Edinburgh in 2004, the Shoebox Zoo ended up in the possession of an eleven year old girl named Marnie McBride (who had recently moved to Edinburgh from Denver, Colorado). Toledo created dark versions of the animals and was able to convince Wolfgang (who was still bitter towards Michael) into aiding him in his quest.
However, later in the series, Wolfgang turns against Toledo and reconciled with his father. Angered, Toledo, in front of Marnie, Michael and the other members of the Shoebox Zoo, threw Wolfgang into a fireplace, where he was reduced to ashes (which also resulted in the death of Wolfgang's dark counterpart).
At the end of the series, Marnie was able to destroy Toledo by giving him a fake version of the book, thus avenging Wolfgang's death.
Around a year later, Toledo returned as a ghost and killed Michael and possessed a woman named Aurora Dexter in order to investigate a second prophecy to create the Dawn Queen.
However, after the prophecy is complete and Toledo gets his body back, Aurora forces him to serve her. Toledo later betrays Aurora to obtain the book, but is killed when Marnie destroys it.