On screen, HeeJae is always energetic, bubbly, positive, friendly and open-minded. She can also be sometimes a bit stubborn or opiniated (especially when it comes to her past boyfriends behaviors). She doesn't like following trends.
Off-screen, as seen in the background of some videos, she seems actually relaxed. She also said that she stays a lot in her bedroom, confirming that she is not as hyper-active as she might sound on shows. This being said she and her friend YeonJin did say that she is "in real life" the same as on screen.
Actually, besides dance, HeeJae dislikes doing sport, but she likes to watch baseball (and potentially soccer?) games on TV.
With her friendly personality, she has predominantely male friends, but says that it does not equate to having boyfriends often. She actually used to date very little when she was younger, and, as of July 2020, was self-proclamed single.
For hobbies, she likes to watch Netflix (in particular "Elite") and she play mobile games, as well as Overwatch on PC.
She has visited two foreign countries until now: China (twice, for performances) and Thailand (twice, for holidays).
It seems that she listen to a mix of western pop stars and KPop idol groups (BTS and Twice notably, she was a Shawol -SHINee fan- when she was younger, she attended the Exo streaming concert from CBP in 2020, Oh My Girl, (G)-Idle, SNSD, Secrent Number...).
She used to go clubbing but finds it to noisy now, and prefers to have a drink in a calm place.
She is very adventurous when it comes to food and like to try every types of food, no matter the look or the smell. She tends to prefer cheap food to fancy food.
She has multiple ear piercing,. She mentioned that it helps her get her stress down. On the other hand, she is too worried that it might hurt to get a tattoo.
She likes to wear various type of well-styled clothes but do not wear skirts. She also likes to wear hair extension and eyelashes extension because she considers hers to be too thin and too short.
As for anime, she is known to like OnePiece.