Alembic is from the city of Utopia, one of the outer planes that is taken up entirely by a single city. It is the city of law, where legal scholars debate the entirety of the law, including it's finest points, eternally.
Alembic's talents for magic revealed themselves at a very young age, and after getting tested and filling out the paperwork, his parents placed him in training to begin focusing and harnessing his power. After passing all of the beginner and intermediate training courses, Alembic was finally allowed to be assigned to a mentor who finished his training.
Once he had finished training, Alembic quickly found a job with the Lancelot Society; an organization apparently created by Abadar himself to study the mortal concepts of adventuring and adventurers. The members were broken up into teams, with each team taking missions that were similar to the sorts of missions a group of mortal adventurers might undergo: finding missing people, saving towns from attacks, and delving into ruins to recover lost relics; this just was happening among the planes, and the most common foe they would face would be demons and devils.
Alembic worked for several years as part of a team that consisted of himself, a Tiefling paladin of Abadar, a Shabti priest of Iomedae, and a Suli martial artist who was attempting to learn every form of unarmed combat in order to please his lord Irori. During their adventures, the group uncovered and stopped a demonic invasion of the elemental plane of fire, lead by an inquisitor of Grazzit; they stopped a near war between the leaders of the planes of fire and water by showing how a rogue Solar was manipulating events in an attempt to have the two planes go to war with each other so that the Solar's forces could swoop in and pounce on the survivors. They also did their fair share of more mundane adventuring work: clearing ruins, finding lost people and relics, and so on.
This all changed when he was pulled from his group and told that he was being sent on special assignment to Golarion on the prime material plane. Apparently there was a great deal of trouble brewing, and a holy knight of Abadar has prayed for assistance from his god. Alembic was meant to be that assistance. Collecting his belongings from his dwelling (and filling out the paperwork in triplicate in order to break his lease), Alembic stepped through the portal and onto Golarion.
