Jeongyeon was taking a walk by herself. Alone. If it was like before, she wouldn't be by herself. She wouldn't be alone because a certain girl always walk with her.
But it wasn't like before anymore. A lot has changed ever since that happened.
Whenever they take a walk, she's the one who always brighten up the atmosphere. But she's the older one! As the older one, she should brighten up her mood.
But she failed at that. She cries as she regrets not being a reliable unnie for her. She cries as she regrets always relying on her.