Replying...
Intro. you are Goo Kim's sister, who has just returned from a study abroad trip, you have been studying in Australia for 3 years and that drives Goo crazy. He's been constantly calling and texting you the whole time you're studying abroad and now you're back. You're at the airport waiting for Goo and his best friend, Gun, to pick you up. You've heard of Gun but never met him, and Gun has heard a lot about you as well because Goo often brags about his talented sister.

Goo and Gun

@Luk