The Shiunji family with their seven children reside in a mansion within Tokyo’s Setagaya ward. The eldest son, Arata, is tired of being pushed around by his five sisters and daydreams of a life without them. That is, until Arata’s father reveals a shocking truth—Arata isn’t biologically related to his sisters! The siblings’ relationships will be tested as they navigate life in this new light.
Noah must leave her city, boyfriend, and friends to move into William Leister's mansion, the flashy and wealthy husband of her mother Rafaela. As a proud and independent 17 year old, Noah resists living in a mansion surrounded by luxury. However, it is there where she meets Nick, her new stepbrother, and the clash of their strong personalities becomes evident from the very beginning.
Natsuo is a high school boy who is experiencing the crushing despair of unrequited love. To make matters worse, the person he is in love with is his teacher, Hina. In an attempt to lift his spirits, he attends a mixer where he meets a girl named Rui. The two sleep together, expecting never to see one another again, but fate has other plans. His life suddenly becomes more complicated when his father comes home and announces he has remarried a woman with two daughters whom Natsuo has met before: Hina and Rui!
Ah, high school. Is there any better place to start fresh after a horrible middle school relationship? Nope! Not unless your ex ends up at the same school as you and is now your stepsibling. What was supposed to be a sanctuary of peace where I could avoid ever seeing her again has become a living nightmare! Everywhere I look, I see her—in my house, in my school, in my class. There's no escape! She even claims that she's the older sibling. Like hell she is! But I won't lose to her. After all, I'm the older brother in this new family situation. That's right, we're family now. No matter how much we may have thought we loved each other before, we saw one another's true colors and realized we weren't meant for each other. That's why even though we may keep up a buddy-buddy sibling act for the sake of our parents, things will never go back to the way they used to be.
Bai Luo Yin and Gu Hai are forced into each other's lives by their parents' marriage, but neither expects what their bond will become.
After 8 years apart, Golf and Bank return home, but Bank is now torn between his past love, Golf, and his fiancé, Jackson. Who will he choose?