Handsome cool bloodthirsty Duke who is supposed to kill an enemy suddenly fall in love (because of unknown magic) with a girl who he’s supposed to kill ... VERY INTERESTING AND CUTE ... ITS SO FUNNY HOW THE COOL AND SWEET DUKE PERSONALITY SWITCH EACH TIME
https://tkor.sale/왜-이러세요-공작님
Why are you doing this, my Duke!? Webtoon