Shim Cho Hee @ Cho Hee

-She is 22 years old. She likes to spend her time with her brother, Shim Changmin also known as Changmin from TVXQ but he always busy with his schedule. As a result, she always follows him anywhere. The reason why she follows him is because he wants her to be with him everywhere and everytime. No one knows she is Changmin's baby sis except their family, TVXQ, JYJ, TVXQ's manager, her bestfriend and SM idols. Everything change when HE knows that she is his sunbae's baby sis.

Nam WooHyun @ Woohyun

-He is 24 years old. Despite of his age, he likes to do aegyo to Inspirits/girls but hates to do aegyo to his fellow members except Sungkyu. He is one of the main vocalist in Infinite. Likes to hang out with TVXQ during his practice time. He is the chef and the mom in Infinite. He is the most greasiness person but turn quiet and shy when he sees HER. He never realises that he fell in love of first sight with HER.

Shim Changmin @ Changmin

-A member and the maknae of TVXQ. He is an overprotective brother. He cares about Cho Hee so much until he beg the CEO and his manager to let her come with him but he never told you that. He never allows any boys hug you but you never listen to him. Wants to tell the world that you're his baby sis.

Infinite

-Consist of Sungkyu, Dongwoo, Woohyun, Sumgyeol, L and Sungjong. Being transferred from Woollim Entertainment to SM Entertainment. The most noisy (except Woohyun) person Cho Hee ever know. Knows that Woohyun likes Cho Hee. They care about Cho Hee since she is Woohyun's crush and their sunbae's baby sis. Likes to hug her even though Changmin forbid them to. They like to hang out with Cho Hee and always buys you a lot of ice creams.