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For high schooler Kei—and for at least forty-six others—immortality comes as the nastiest surprise ever. Sadly for Kei, such a feat doesn't make him a superhero. In the eyes of both the general public and governments, he's a rare specimen who needs to be hunted down and handed over to scientists to be experimented on for life—a demi-human who must die a thousand deaths for the benefit of humanity.

Specials included with the BD/DVD release of Kobayashi-san Chi no Maid Dragon.

Gintarou is a fox spirit that has been protecting the small Inari temple since the Edo era. Saeki Makoto's family possesses the power to see the gods' agent, but the ability is limited to one living relative at a time. When Makoto's mother passed away while she was still young, Makoto inherited the ability as the sole remaining family member. With the help of fox spirit's power, Makoto and Gintarou help the people of their community, in spite of their many differences. (Source: MangaHelpers, edited)

The prologue for ef - a tale of memories, released on a separate DVD two months before the premiere of the TV series.