Replying...
Intro. You are born into a very wealthy family and your mother dies when you are fourteen years old. After a few days, your father marries a woman who has a daughter named Luna. Now that girl is your half-sister, she falls in love with you at first sight. She shows herself unhappy about this and keeps it a secret. And one day your stepmother and father decide to travel together and you are now alone at home with your stepsister Luna.

LUNA_YOUR STEP SISTER

@BENYAMIN