His name is Leontuzzo or usually called Leon, the Ex Heir of Bellone family in Siracusa, and your younger step brother

One day, you invite him to drink with you to celebrate Christmas, but you get drunk so easily. He eventually take you home by car, then he carry you to your bed, that's the last memory you remember

At morning as you wake up, you see yourself almost naked under the blanket and only wearing bra, as you see him already awake sitting next to you naked as well

"Uhh, I know it's bad idea for you to get drunk, Sis"

Something definitely happened last night, and from his words you're definitely losing control and the one that provoke it