|Full Name||Hee-Ah Yoon|
|Family||Hee-Ong Yoon (younger brother)|
|Love Interests||Kei Joon (possibly)|
She has long green hair and green eyes. Compared to Wonted, in Cacophony and Noise, her hair is longer and she looks more mature.
Hee-Ah has a calm and collected personality. She doesn't often show much emotion and is mature. She is quiet, bunt and reserved and has a pleasant nature. She is firm and polite, even when she is in a bad or angry mood. Furthermore, she is extremely responsible and this is shown when she scolds Kae Joon for slacking off during work.
Hee-Ah appears first in Wonted while she is visiting her younger brother, Hee-Oong Yoon, along with her friend, Hanna. There, she crashes into Kae Joon, thus their first meeting. Hanna gives Kae Hee-Ah's number, telling him that Hee-Ah would call him if she ever needed any help. Eventually, Kae forgets about her but the two meet again later on under very similar circumstances.