Tsuihou Sareta Bannou Mahou Kenshi wa, Oujo Denka no Shishou to Naru

Solon, who has been exiled by his comrades, met the secluded and lonely princess, Philia. She believed in his words that ' as long as you have knowledge of magic you can be free.' With the request of his former mentor, Solon became the girl's private tutor. To protect the girl from assassins, they were sleeping together inside a room with a barrier. They went everywhere together, from choosing magic staffs to fighting ghosts. With that, Philia’s training as a magician has started, but it looked like the main figure of the Empire’s schemes was starting to move… A magic swordsman who was despised because of his versatility and inferior skills met the uncommon princess. Source: MU