The Magic in this Other World is Too Far Behind! Volume 2 by Gamei Hitsuji

Finally striking out on his own, Suimei departs the castle and heads to the capital to join up with the local branch of the Adventurer’s Guild. He meets a beautiful and talented young woman there who’s received a strange bit of advice from the oracle. They both join up, and Suimei begins his new life as... a totally average mage in this world? What is he thinking? And what of Reiji, Mizuki, and Titania? How will any of them handle their first encounter with a real demon?