In the world of Ling Yu(Spiritual Field), there is a continent named Chilan(Red Tide), where warriors and their Spirit Weapons are classified into different levels. Families and clans follow a strict hierarchy, too. Under the leadership of the Xuantian Union, human warriors and the Evil Clan have been engaged in brutal fights on Nether Battlefield for hundreds of years. A Soul-devouring Beast sneaked into the Chilan Continent through a crevice on the Nether Battlefield before it ruthlessly slaughtered the Feng Town and the Gao Town. Qin Lie, a young man from the Ling Town, together with Ling Yushi and Gao Yu whom he had grown up with, was commanded to help the Xuantian Union in the conquest of the Soul-devouring Beast. He did not anticipate that he would be swallowed into a great conspiracy. To protect his friends and to rescue the one he loves, the powers hiding in his veins are awakening.

Shougo Mikadono's father has just passed away, and now he must become the head of Mikadono Group, his father's company. After completing the training to take over, there is just one other stipulation he must adhere to: he will need to find a girl he loves at his new school and marry her by the time he graduates high school. Shougo transfers to Miryuin Private Academy, and it seems like he has many girls to choose from, such as Konoe Suruma, the class representative as well as his first new friend; Miyabi Kannagi, a standoffish but kind girl; Rinka Kunitachi, the student council vice president; Mei Sagara, who runs a cafe and dresses like a witch; and Mana Tendou, the student council president. However, there is a complication: one of them is his long-lost half sister, and he has no idea which one, so how can he become romantically involved with any of them? [Written by MAL Rewrite]

Kagemori Mamoru is a dowdy boy whose hair is disheveled and who wears thick glasses, but he is actually the son of a ninja family. They have protected their neighbors, the Konnyaku family, secretly for 400 years. Mamoru has personally protected their daughter, Konnyaku Yuuna, since they were in kindergarten. When Yuuna is in trouble, Mamoru puts on ninja suit and turns into a competent ninja to help her.

Taito has been really sleepy lately, and keeps dreaming of a female vampire who says she has given him her "poison." Sometimes he even thinks he hears her voice when he's awake. But after surviving an accident that should have killed him, Taito's world changes drastically and he realizes that his dreams are more real than he thought.