Is It Wrong to Try to Pick Up Girls in a Dungeon? On the Side: Sword Oratoria, Vol. 14 (manga) — Fujino Omori

Locked in heated battles, Tiona and Tione face off against remnants of their poisonous past...With Aiz's hands full opposing Ishtar Familia's captain and Lefiya held hostage, the situation seems dire.
But as Loki unravels the behind-the-scenes workings of Port Meren's monster infestation, reinforcements arrive- Finn and the rest of the boys are itching for a tussle and ready to show Kali Familia just who they're messing with!