S-kyuu Boukensha ga Ayumu Michi: Tsuihou sareta Shounen wa Shin no Nouryoku "Buki Master" de Sekai Saikyou ni Itaru

The adventuring party Sacred is quickly becoming famous for its incredible heroic exploits—and its supremely talented leader, Sasha. Almost no one remembers that Sacred ever had a co-leader: Hyse. Once Sasha's childhood friend, he was booted from the party, reduced from his already tenuous position as workhorse to plain deadweight. Devastation at the betrayal and shame over his own weakness drives Hyse to pour his bitterness into learning his Ability, an unfathomable power not even he fully understands. Now mistrustful but determined, Hyse steps up to take on the world—and the comrades who abandoned him. (Source: J-Novel Club)