Kuni ni Saikyou no Barrier wo Hattara Heiwa ni Narisugite Tsuihou Saremashita. Sono Barrier, Eizoku Janai yo?

Synopsis:

Shield, a young guy, has been despised and is limited to using the novice magic "Barrier". Because of his fiancé's deceit, he gets deported even though he put constructed an unbreakable barrier to defend the nation. But before he knew it, a bunch of vicious demons were after him, he had defeated the fiercest dragon (a young girl), and he was being courted by attractive women from various nations!? Shield, a young man who can only defend himself but whose defense is the greatest, weaves a new kind of fighting action!