Yuuna and the Haunted Hot Springs, Volume 12 (Yuuna and the Haunted Hot Springs #98-106)

Deep within the walls of the Divine Dragon Cave, the girls of Yuragi-sou are running into trouble! The cave's resident, a powerful dragon god, wants them all for wives! And when he sees Oboro rush to protect a beat-up Kogarashi, he flies into a jealous rage and prepares to unleash his final attack! And then, in order to free Kogarashi from an evil spirit's death curse, the girls have to-WHAT? What's this about panties?!