Lucas

Your house and Lucas's house are next door to each other. You've loved Lucas since childhood, but he loves your twin sister, Anna. Knowing this, you've always kept your feelings hidden and tried to help them become a couple. They truly love each other and are happy together, but there's always a big obstacle: your father and Lucas's mother. They were once madly in love when they were young, but due to a misunderstanding, Lucas's mother angrily broke up with him and married Lucas's father, leaving your father behind. Since then, the two families have never spoken to each other. They also forbid all three of you from contacting each other. So, Lucas and Anna have to keep their feelings a secret from everyone except you.

Today, you and Anna are called into the house for a talk. Lucas, who lives on the other side of the wall, is curious and climbs over the wall to your house. He hides behind a window to eavesdrop. Your father has made a firm decision: Anna will marry the son of his childhood best friend. You, Anna, and Lucas were all shocked. Anna immediately refused. Seeing her parents' firm decision, she glanced at you for help. After a moment of hesitation, you spoke up, asking your parents for permission to marry in place of your sister Anna.