"I promise I'll visit this Christmas." Seulgi raised her hand to ruffle Joohyun's hair, who was hanging her head low.

They were at the train station, standing in front of the train's entrance, which would take Seulgi to Seoul in a few minutes.

Two years had passed and it was time for Seulgi to leave Daegu for college. Well, Taeyeon, too, enrolled in the same university as Seulgi, but she was thinking of driving back home every weekend because Joohyun was home alone and Joohyun whined when Seulgi said she couldn't go back home along with Taeyeon because she lived in a dorm.

Taeyeon stood there, watching Seulgi trying to convince her younger sister that she'd be here again in no time. Taeyeon knew her sister had grown attached to her best friend. She remembered how excited Joohyun was to finally attended senior high, meaning that she could join the famous cheerleader club of Daegu high to impress Seulgi as Krystal Jung did. However, Taeyeon told her she didn't have to do that because Seulgi didn't even bat an eye. But since Joohyun insisted, she gave up.

They heard the last announcement for Seoul and Seulgi quickly ped her backpack to pull out her volleyball jacket, "you can have this," she smiled warmly at Joohyun and swiftly helped her to wear it.

Joohyun didn't say anything as she was surprised at the sudden action. She lifted her head, and her eyes met the older girl's after she finished zipping the jacket to the top.

"Seulg-"

"I have to go now," Seulgi was the first one to look away to hugged her and she also gave Taeyeon a quick hug before stepped onto the train, giving them a wave for the last time then walked further in and not looking back anymore.

Joohyun watched the train left sadly. She walked closer to her older sister and knocked her body onto her, which Taeyeon caught instantly and pulled her into her embrace. Joohyun buried her face on her shoulder and closed her eyes to prevent any tears from falling. Joohyun would call herself dramatic right now but that was how she felt.

She was sulking. She was mad at both herself and Seulgi. She was mad at herself for sulking and refused to talk to the older girl when she was standing right there in front of her five minutes ago. And she was mad at Seulgi for not telling her sooner that she was leaving. Sure, she'd come back for any holidays but she should wait for those days to come instead of randomly barging into Seulgi's house and spend the day with her whenever she wanted to.

Taeyeon understood. Joohyun was no longer a kid, though, in her eyes, Joohyun would always be her cute little sister whom she loved so much even though she refused to say it out loud.

A Teenager. Where most puberty wou