The Hero Proposed to Me

Male lead, why do you propose to the villainess and not the heroine?
Having the strongest man in the empire as father, the most beautiful woman as mother and three arrogant brothers; there were beauty, power and irreducible wealth no matter how much you use it. I came to possess the villainess who had everything in the novel, ‘Siel Valentine’.
In the original story, the heroine was the adopted sister of Siel. In the original story, Siel had an unrequited love for the prince who chose her sister. Blinded by jealousy, Siel bullied the heroine and so was executed in the hands of the male lead prince.
In the original story, jealousy along with tormenting others caused her to get beheaded by the prince. Thus, I tried to get my sister and the male lead together……
“Miss Siel, please marry me.”
Male lead, why are you proposing to me?