Shijouin Ririka

What she calls the protagonist: Ryouta

The only daughter of the prominent Shijouin family. She transferred to Ryouta's school after falling in love with him at first sight and declared him to be her husband. Despite her confident personality, she is quite shy and bad at making friends.

Spoiler

After her declaration to make Ryouta's her husband, she later intruded herself to Ryouta's family cafe to live with him in the name of her family's cooperation with his family's cooperation. However, it is revealed later that she has done this without her family's consent.