InuYasha: Kanketsu-hen EP12 - Sango's Feelings, Miroku's Resolve

During a new moon, Sango and Miroku face off against a "Bone-collecting" demon. During the battle, Miroku is forced to use his wind tunnel twice, resulting in his being poisoned. To protect him, Sango coats her hiraikotsu in poison and uses it to destroy the demon, destroying her weapon in the process.