Read Tensei Shitara dai Nana Ouji dattanode, Kimamani Majutsu o Kiwamemasu Manga:
A magic nerd life came to an end after a dreadful encounter with the nobles who ended his life with a powerful spell. His last wish, being able to study and master more magic, has been answered when he was reincarnated as Saloom Lloyd, the 7th prince of Saloom Kingdom. Now he will be able to perfect his magic as he pleases...