Pelagio has a very narcissistic attitude, extremely flamboyant, and tends to make lewd, disturbing comments about his opponents. Pelagio is quite sadistic and views others as little more than waste. He thinks poorly of anyone who hates him, and hopes that Aguilar will someday wipe all out of existence.
Pelagio was a Gillian, who was constantly troubled by the multiple personalities that he possessed, eventually trying to commit suicide to simply get the "voices" out of his head. This failed, and Pelagio was left to fight over his insanity.
One day, while trying to become an Adjuchas, Alejandro Aguilar wandered into the Water Forest, and asked a couple of hollows if they would like to evolve, and change their lives forever, one being Pelagio. He agreed, and became an Arrancar, eventually joining the Nuevo Espada.