The Magic in this Other World is Too Far Behind! Volume 5 by Gamei Hitsuji

After the dramatic events that transpired in the imperial capital, Suimei feels like he’s gotten what he can out of the Empire for now. Following a clue discovered in the book Felmenia brought to him from Astel’s royal library, he sets off on the next leg of his journey with the court mage, spirit swordswoman, and reformed dark magic user in tow. What awaits them in the Saadias Alliance? And what’s this about a third hero? Moreover, what of the dark forces that are now working in the shadows?