College student Aki, a sexually uninhibited sub, feels the strong gaze of an unknown person while engaging in sexual play - the “eyes of the beast” unique to Doms who makes the subs kneel and be dominated. Since then, Aki has not been able to forget those eyes. Mitsuru, Aki's younger childhood friend, has always had feelings for Aki, even though he knows subs are not compatible with normal people. When Aki chooses to work part-time for a clinical trial for suppressants to earn money for university tuition and decides to find a Dom who will live with him for two months, Mitsuru finds out about this and stops him, his eyes being the same as those unforgettable "beast eyes"...!