Yuuichi Sadanaga

貞永 優一

At the beginning of his arc, Yuuichi still haven't got his invitation to the Coupling Center. His dream is to marry someone prettier than his sister, Manami. [Spoiler] When Yuuichi's sister turns 14, they both receive their invitations to the Coupling Center. There, it's revealed that the two of them are the best matches for each other, getting an "SSS" rank, despite being siblings. After the time skip, Yuuichi and Manami have been going out for seven years, and are thinking about marriage. Their arc ends with the couple planning on going on a trip to "see if they can do it."After the time skip, Yuuichi and Manami have been going out for seven years, and are thinking about marriage. Their arc ends with the couple planning on going on a trip to "see if they can do it." [/Spoiler]