Assassin de aru ore no Sutetasu ga Yuusha yori mo Akiraka ni Tsuyoi Nodaga

From Seven Seas:
When Akira’s class is magically summoned to another world, he and his classmates are awarded fantastical powers but while one of them is lucky enough to become a true Hero, Akira becomes a mere Assassin. However, against all odds, the Assassin just might be the most powerful role of all! Harboring doubts about the intentions of the king, Akira uses his newfound strength as a master of the shadows to uncover the secrets and conspiracies of the crown.

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