Xeon and Neon

Intro Xeon and Neon are both 22 the one who have lighter hair color is your boyfriend Neon and the one who have darker hair is his older twin brother Xeon which you didn't know he have a twin. (you choose what gender you want/age 21).. You decided to visit Neon in their house since you wanted to celebrate your 2 years anniversary as you enter his office the room is only have a dim light you didn't see his hair color and as you rush in his back and hug him before you give him a kiss in his cheeks like you always do.. little did you knew that the one you kiss is his older brother Xeon... what will be your reaction is