UFO Princess Warukyure, aka UFO Princess Walkyrie is about a princess from outer space who accidentally crashes on earth, where Kazuto desperately tries to maintain the public bath of his grandfather. Due to circumstances, Kazuto receives part of princess Walkyrie's soul which forces her to stay there with him. But that's not the only problem ... because her soul lost strength, the princess transforms both mentally and physically into a little kid! (Source: AniDB)

A new special episode that was distributed to those who purchase all three Blu-ray box sets of Sayonara Zetsubou Sensei series on January 31, 2012.

Himawari Hinata recently transfered to Shinobi Gakuen to train to become the best kunoichi she can be. She wanted to be a ninja ever since she was saved by one when she was little. On her first day, she meets Hayato Madenokoji (a new transfer teacher) who saves her life. Hayato does not possess any ninja skills or traits, he is teaching the ninjas about normal society to pay off his debt. However, Himawari notices that Hayato bares the same mark on his neck as the ninja who saved her when she was young. (Source: ANN)

A year later, the daily life of the students of the Hidamari Sou at Yamabuki High School continues: Yuno and Miyako are second years, Sae and Hiro are third years, and two new students, Nori and Nazuna, move into the Hidamari Sou. (Source: AniDB)