Volume 30 consists of Chapters 120-123.
Chapter 120 - Queen of Pirates
Sunako and the guys are watching television when a feature about a gem formerly belonging to a female pirate. The show states that the gem now belong's to Mine Nakahara, Sunako's aunt. Incidentally, Auntie just arrived and announces her decision to stay with them for a while to relax while she can't find a guy she would want to date. The guys immediately worry about Auntie discovering that her niece has not become a lady yet and think of a plan to find a new boyfriend for her. Auntie meets a man while out with Sunako. The man appears to have fallen for her Auntie so Sunako, and Kyouhei as well, help him until the man successfully proposes to her Auntie. On the day of the wedding, the man reveals his true self and steals Auntie's gem. In the end, Auntie throws the gem to the water and tells him to recover it from there.