Oh My Goddess! Omnibus 3

Strange, cute, and charming new characters are around every corner in Oh My Goddess! Omnibus Book Three! First, the blond-bombshell demoness Mara descends with a wicked plot to possess the body of Keiichi’s little sister, Megumi... which leads Skuld to build a new character, Mini-Banpei RX, to combat their infernal rival! Then, at a mountain resort, the ghost of a long-dead lovely maid takes form to try to get Keiichi to honor a promise his grandfather made to her, and Mara strikes back by conjuring a trio of killer ninja masters... ninja masters only one foot tall! Collects volumes 7-9 in omnibus format.

Source: Anime News Network Encyclopedia