Excelsior Spellheart backstory

Excelsior Spellheart is a male human wizard. He grew up in absalom, the son of 2 powerful magic users. His magical ability came natural to him and he was a prodigy in every sense of the word. He was granted early acceptance into a magical college called the arcanamirium. It was there he made friends, honed his skills, and expanded his studies. He was an excellent student and had good relationships with all of his professors but he grew exceptionally fond of one in particular. His conjuration professor,  Esiar Daednu, was a beautiful woman, smart and a bit flirty, seemingly taking a liking to Excelsior as well. She would constantly praise his abilities, comment on what a natural he was, and fawn over what he could be capable of. Beaming with confidence from all the praise, and eager to please his favorite teacher, Excelsior would often do anything she suggested, or believe anything she said. A bit cocky and a bit immature, one day his naivety had led him down a dark path. Esiar had asked if he knew anything about necromancy and if he knew about the unfathomable power that lie in that taboo school of magic. He wasn't too keen on the idea of raising undead, but he enjoyed the idea of unlimited power and Esiar had an uncanny way of getting what she wanted. He willingly subjected himself to a ritual, conducted by Esiar, under the guise of academic pursuits, to further his knowledge quicker. However, the rituals true purpose was to control his mind and turn him into a thrall. Esiar, in reality, was no professor at all. She was a high standing member of a resurgent group of necromancers called The Whispering Way, tasked with infiltrating the college and mind controlling promising students to be thralls to raise undead minions to bolster the army of the infamous lich lord Tar-Baphon, the whispering tyrant. Excelsior was enthralled for about a year, learning powerful necromancy from Esiar and raising undead, until one day, Pharasma appeared to him in a dream. Her godly intervention was enough to break his mind free from the enthralling magic. When he awoke, his memories from the last year were hazy and unreliable, some memories missing completely. He was fully aware he was working with a group of necromancers to raise countless undead, but the how and why were a mystery. He was able to escape from the necromancers and venture out into the world, now a devout follower of Pharasma, sworn to destroy all undead,  grateful to her for her role in freeing his mind. He is slowly piecing his memories back together, as he makes his way back to the arcanamirium in absalom.