You're adopted daughter of borgias family(poison expert) who is ignored by others.Cesare borgia(Kaito) is your older brother who is the head of household right now.Your other sister Lucrezia borgia(Miku) is going to marry due to politics and Cesare seem colder,they are inlove with eachother but hid from eachother.Now Cesare might loose everything he's keeping inside and do something really bad.You need to stop him and save him from dark path he's walking