Marin and her younger sister Urin are seafolk who happen upon something quite strange: a beautiful silver ring lost beneath the waves. The kind-hearted Marin, intent on returning it to its owner, drags a reluctant Urin along with her to the sky world despite reminders of a turtle elder who left for the surface and never returned. After locating the ring's owner, Kanon Miyamori, they learn that Kanon had tossed it into the sea after her boyfriend dumped her earlier that day. Though Marin insists that such a lovely item should not be thrown away, Kanon discards it once again. As they search for the ring, Urin becomes separated from the other two and accidently breaks the seal on a stone coffin, releasing an evil being known as Sedna. Sensing Sedna's release, the formerly missing turtle elder, Matsumoto, reveals himself to Kanon and her companions, naming Marin as the Priestess of the Sea. Together with the Priestess of the Sky, she has the power to seal Sedna away again. And as luck would have it, during an encounter with one of Sedna's minions, Kanon discovers that she is the Priestess of the Sky. Though Kanon is hesitant, she and Marin decide to work together to save the world from the evil that threatens it.

Protagonist XiaoFei used to be an ordinary guy from H city. After the spring water was contaminated with a virus, however, he unexpectedly encountered an unprecedented crisis. The people living in H City became zombies one by one, devouring each other, and gradually evolving. Can XiaoFei escape from H city and meet up with his girlfriend Wei? The story now begins...

Lux, a former prince of an empire named Arcadia that was overthrown via a rebellion five years earlier, accidentally trespasses in a female dormitory's bathing area, sees the kingdom's new princess Lisesharte naked, incurring her wrath. Lisesharte then challenges Lux to a Drag-Ride duel. Drag-Rides are ancient armored mechanical weapons that have been excavated from ruins all around the world. Lux used to be called the strongest Drag-Knight, but now he's known as the "undefeated weakest" Drag-Knight because he will absolutely not attack in battle. After his duel with Lisesharte, Lux ends up attending the female-only academy that trains royals to be Drag-Knights. (Source: ANN)

A series of comedic shorts featuring chibi versions of the characters of the main show.