Is It Wrong to Try to Pick Up Girls in a Dungeon? On the Side: Sword Oratoria, Vol. 4 (manga) — Fujino Omori

Deep in the dungeon, the rogue town of Rivira is under attack by a new breed of monsters and it's up to the adventurers to defend it! Luckily, some of Loki Familia's best have the situation well in hand. But when Aiz faces-off with Hashana's murderer, she has a personal score to settle as well - why does this murderer know "Aria"!?

After an unsettling defeat, Aiz's desire to level-up and become "strong" burns inside her more than ever, pushing her challenges in the Dungeon to the extreme. So her request that Finn and the others leave her behind in the lower levels must be for her singular goal...right?