Description: During his student years, the protagonist lost his entire family in an accident. He was then taken in as a foster child by Hanazono Ryuzo — his late father’s close friend and a wealthy businessman. In place of the constantly busy parents of the Hanazono household, he looked after his stepsisters Yuka and Hotaru while diligently focusing on his studies. Years later, after the protagonist became an adult, Ryuzo offered to formally adopt him. However, he declined the offer, chose to leave the Hanazono family, and began living independently. Five years after that—— While living in a shabby rundown apartment, the protagonist receives a call from Ryuzo after a long time. “Could you move in and tutor my daughters?” Although bewildered by the sudden request, he couldn’t refuse Ryuzo — the man to whom he owed so much — and agreed to the proposal. Yuka had just entered ○ Academy, and Hotaru was currently studying hard for the ○ Academy entrance exams… The two sisters were now living away from their parents in a luxury apartment in central Tokyo. The contract period is one year. After finishing his move, the protagonist reunites with the two sisters, who have grown into beautiful young women.