On her 16th birthday, Himari Momochi receives a letter stating she has inherited a mansion called the "Momochi House." Having been raised in an orphanage, this mansion is the only thing left of her real family, so Himari pays no mind to the rumors that it may be haunted. Upon entering it, she meets Aoi Nanamori and his companions, Ise and Yukari, who all seem to be squatting in her new home. Although they warn her to leave the house, Himari vows to be the one to make them leave instead. But soon, she is attacked by youkai and finds out that the house sits in the space between the world of the living and the spirit realm. Even more surprising, Aoi was chosen to be the guardian of the house—a position originally meant for Himari. But this great power came with an awful price: Aoi can never leave the mansion, and his existence in the human world has been erased. Ignoring his pleas for her to leave the mansion, Himari promises to help Aoi break the housebound curse as she begins living under the same roof as him.

When mundane office worker Kiyoshi Adachi turns 30 years old, he discovers that he has gained the ability to read minds due simply to remaining a virgin for his entire life. The caveat, however, is that he must make physical contact with a person to know what they are thinking about. Adachi believes there is no real use for this power until he accidentally hears the thoughts of his coworker, Yuuichi Kurosawa. Charismatic and dependable, Kurosawa is the star of Adachi's team at work, earning praise and admiration from everyone at the office. But deep within, Kurosawa harbors an intense one-sided crush for the gloomy Adachi—a fact that Adachi only learns because of his ability, and knowledge he tries to respectfully disregard. As Kurosawa treats Adachi with kindness and affection he has never experienced before, Adachi finds it increasingly difficult to ignore his coworker's genuine advances.

Even though Sasaki's droll corporate life is constantly filled with work, it leaves him tired and unfulfilled at the end of every day. In search of some companionship to fill the emptiness in his life, he visits a pet shop on a whim, not realizing he's about to change his life forever. After settling on an adorable bird and bringing it home...his new roommate reveals that it's actually an incredible sage from another world who promptly bestows Sasaki with supernatural powers as well as the ability to cross between worlds. All Sasaki wants to do is use these newfound powers to live in peace and comfort, but there are more than a few colorful characters who might get in the way of that...

Sixth season of Cardfight!! Vanguard: D Series.