My Status as an Assassin Obviously Exceeds the Hero’s

Oda Akira, a high school student who excels in erasing his presence, was summoned along with his classmates to another world. In this world of sword and magic, Akira and his classmates were asked to become heroes and bring down the demon king. Having a bad feeling about the king and the princess who asked them, Akira uses his special skills to sneak into the king’s library, in hopes of discovering the truth. Whether to help or abandon his classmates who knew nothing, it all depended on Akira. — Description from novelcodex.org