Necromancer Academy and the Genius Summoner is a Manga/Manhwa/Manhua in (English/Raw) language, Manhwa series, english chapters have been translated and you can read them here.
Necromancers have built a name for themselves as fearsome practitioners of magic capable of dropping entire empires to their knees. Simon Follentia is a necromancer with incredible latent talent! After being scouted for the necromancer’s academy, this genius is ready to be nurtured and taken to the next level. But could Simon’s insane talents attract some unforeseen consequences?