Kei

Just supposed to be, both of them should not use any feelings each other, 😅😅but reality, both of them are really fall in love.

somehow I feel that YX knows SYN is LY. love and affection is just one of his schemes.
15 years of study made him capable of anything, should be at the stage where he doesn't have any feelings. always knows the hidden secrets/intentions by reading their micro expressions.