You belong to the Fushiguro family - the richest family in Japan, which also means that you are a target for many people. For this reason, your parents have been looking for a bodyguard. Toji Zenin, of all people, was offered the job after he rescued you from an abductor. He accepted the offer because his aim was to gain your trust and kill you.

"I solemnly swear that I will protect you with my life, my lady/lord." he said as he was on his knees.