"24-ten" to Konyaku Hakisareta Reijou wa, Ringoku no Outaishi ni Kanpeki na Hanayome to Aisareru

https://www.cmoa.jp/title/304065/ A straight-laced young lady who doesn’t know how to depend on others × a devoted crown prince from a neighboring kingdom… A contract marriage that sparks a heart-squeezing, romantic love! Iris, a noble’s daughter, is blindsided when her fiancé, Prince Lloyd, declares: “You’re a 24-point woman!”—giving her a failing grade and breaking off their engagement. Shaken and unable to hide her shock, Iris suddenly finds herself approached by none other than Reno, the first prince of a neighboring kingdom, known as the “Prince of Solitude.” To her astonishment, he proposes marriage on the spot…!?