Yakuza Fiancé: Raise wa Tanin ga Ii English Subbed

Summary:
Yoshino Somei would have been a normal high-schooler if not for the fact that she is the granddaughter of the leader of the Osaka-based Somei Group, the Kansai region’s largest yakuza organization. One day, Yoshino hurries home after hearing of the news about the unification of Kansai and Kanto’s biggest syndicates, the Somei and the Miyama groups. This, according to the article, will result in a marriage of the leaders’ grandchildren—one of whom is Yoshino herself! Despite her best efforts to annul the arrangement, Yoshino has to go to Tokyo to visit her fiancé, Kirishima Miyama, who is unexpectedly nice and charming.