Boku to Senpai no Tekken Kousai

Japan's biggest company, the Koigakubo's daughter, Reijou Himeko has "violence-seeking" eyes. Aoyama Shuuji watches over her, employed by the Koigakubo as her bodyguard. They appear to be "Senpai" and "Shuu-chan" but perhaps... their relationship is not what it seems