The story revolves around a girl named Yuuka, who encounters a being from the depths of the Earth named Chii-chan (a pun of chiteijin, the Japanese word for underground-dweller), and an alien named Ucchan (a pun of uchuujin or alien). The story follows their heartwarming and chaotic everyday lives together.

Rem is an ordinary woman in our world but, in the world of dreams, she becomes a dream warrior, defending humanity from the evils there. When dream demons reach the waking world, she fights them with the help of her pets which transform into a tiger and wolf.

A young man named Akitsu Masato is captured by a secret govt. project known as "Last Guardian". He is told that his life as a normal student was all a lie, and that his real destiny is to be the pilot of a great robot called "Zeorymer of the Heavens". The truth of this is hammered in when Masato sees his parents accept payment for raising him. The Last Guardian is preparing for the resurrection of "Hau Dragon", an organization bent on world conquest. 15 years ago, Hau Dragon built 8 great robots. Each of the mecha represents a force of nature. However, before any of the robots could be used, their creater Kihara Masaki destroyed the robots except for the leader: Zeorymer. He took Zeorymer and an embryo to the government. The embryo became the boy Masato. Now, Hau Dragon has rebuilt the other 7 mecha and wants the 8th. It will be up to Masato and Himuro to pilot Zeorymer and fight against the Hau Dragon, but neither Masato or Himuro are all that they seem. (Source: AniDB)

Set in an alternate version of the Meiji Era, a boy named Sakamoto Ryunosuke returns to Kyoto from Shanghai with his monster (youkai) Nekomaru. The law states that in order to live freely with humans, a youkai must be liscensed. The Kidou Shinsengumi Co. Ltd. is responsible for the capture of unliscensed youkais but must fight with the Tsubamegumi, who resents the new law. It turns out that Ryunosuke is the son of the owner of the Shinsengumis.