Konyakusha (Kari) ni Omae o Aisuru Koto wa Nai to Iwareta node Sono Otouto o Tsure Kaette Muko ni Shita Hanashi

Yurishia is suddenly told by her fiancé, Harold, that he's breaking off their engagement... Going back to when Yurishia was 10 years old, she first met Kairi, her fiancé's younger brother , and fell in love at first sight. She begged him to let her have him right then and there...!? Eventually, the two grow up to be a famous lovey-dovey couple at school!? A beautiful girl who is overly affectionate and completely oblivious to danger x an arrogant and selfish handsome boy... and his unassuming but gentle younger brother, a happy romantic comedy full of doting love.