"Tsuki ni Naku" will take the story content from volume 11 of the manga, which features a visit to an onsen by the members of the Hiizumi Life Councelling Office, while the town's police force have to deal with a new youkai-hunter threat.
This OVA is bundled with the limited edition of the manga (14th, 15th, and 16th).

Bonus episodes on the DVDs featuring the girls on a field trip to Chichibu.

The series is centered on 27-year-old homeroom teacher Mika Suzuki (who only looks about half her age) and the eccentric and colorful students of her class. 
(Source: Wikipedia)

Mars is discovered on a forming volcano island, Heisei; a man with no memory. In reality, Mars is from outer space, and is supposed to gather information to decide whether Earth should be destroyed or not. Along with the giant robot Gaia, and his mysterious images of a woman urging him not to destroy the world, Mars decides to fight for Earth rather than destroy it, even if it means fighting his own kind. But if Mars is killed, Gaia will explode, destroying Earth along with it.
 
(Source: Anime News Network)

Eriko and her friends Yuma and Ayano are excited about entering high school. Their excitement leads to their breaking of the rules when they toured the school before the opening ceremony. They find out their preconceptions about the all female school may not be as true as they had first thought. Despite that, Eriko and her friends are joined by new friends. They aim to get through high school life together.
 
(Source: Anime News Network)

Meet Suzuki Mika, teacher at Okitsu High School. Mika-sensei is a good teacher, but she has a small problem... literally. Although she's 27, she is only 148 cm tall, and has the face of a child. As a result, it is often difficult for Mika-sensei to get anyone to take her seriously.
 
(Source: Anime News Network)

Gold Roger was known as the Pirate King, the strongest and most infamous being to have sailed the Grand Line. The capture and death of Roger by the World Government brought a change throughout the world. His last words before his death revealed the location of the greatest treasure in the world, One Piece. It was this revelation that brought about the Grand Age of Pirates, men who dreamed of finding One Piece (which promises an unlimited amount of riches and fame), and quite possibly the most coveted of titles for the person who found it, the title of the Pirate King. 
Enter Monkey D. Luffy, a 17-year-old boy that defies your standard definition of a pirate. Rather than the popular persona of a wicked, hardened, toothless pirate who ransacks villages for fun, Luffy’s reason for being a pirate is one of pure wonder; the thought of an exciting adventure and meeting new and intriguing people, along with finding One Piece, are his reasons of becoming a pirate. Following in the footsteps of his childhood hero, Luffy and his crew travel across the Grand Line, experiencing crazy adventures, unveiling dark mysteries and battling strong enemies, all in order to reach One Piece. 
*This includes following special episodes: 
- Chopperman to the Rescue! Protect the TV Station by the Shore! (Episode 336) 
- The Strongest Tag-Team! Luffy and Toriko's Hard Struggle! (Episode 492) 
- Team Formation! Save Chopper (Episode 542) 
- History's Strongest Collaboration vs. Glutton of the Sea (Episode 590) 
- 20th Anniversary! Special Romance Dawn (Episode 907)

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