Kyokuten no Honoo Majutsushi: Fireball shika Tsukaenai kedo, Motetai Isshin de Saikyou ni Narimashita

Igni is born into a noble family that aims to be the strongest. At the "Rite of Appropriateness" held on his twelfth birthday, it is revealed that he can only use the elementary magic of fireball, and he is banished from his family home.

Igni lives an oppressed life in the town, but when he is reunited with his grandfather, who was once called the "Pole" and was one of the strongest, the wheels of fate begin to turn... A school magic fantasy of a boy who becomes the strongest just because he wants to be popular.

(Source: Futabasha, translated)