The Demon Sword Master of Excalibur Academy, Vol. 3 (manga)

After a tough battle, Leonis has managed to protect the Seventh Assault Garden from the attack by the Archsage, Arakael. Soon, he gets wind of the Imperial princess-s visit to Excalibur Academy and attempts to make her acquaintance-but meanwhile, in the shadows, the fearsome scheme of the -demon sword wielders- is beginning to take shape.