Jin-ah Sung

Age: 15-17
Occupation: Student

Sung Jin-ah is Jin-woo's younger sister. She is a hard-working girl who usually tops her school exams and has a close relationship with her brother since they are the only siblings in their family.

As she grew with only Jin-woo next to her with her father stranded in a gate and her mother ending up in a coma due to Eternal Sleep Disease, Jin-ah was always on edge whenever Jin-woo was in the hospital and wanted him to stop being a hunter.

Jin-ah was at school on a weekday when a gate opened up inside her school. The school was thrown into chaos with the magic beasts rampaging within the school. Once orcs entered her classroom, they noticed that there was a human emitting magical energy, which was coming from Jin-ah. The orcs who believed her to be a hunter attacked her.

A black veil of smoke appeared from Jin-ah as High Orcs protected her from the lower orcs attacking her. The boss of the dungeon, Groctar, entered and began to attack the High Orcs with all his might. He eventually grabbed the helpless Jin-ah by the neck and was about to kill her, but Jin-woo was able to make it to the school himself and saved her. Thankfully, she had no injuries except the hand imprint left on her neck by Groctar.

After some time had passed since the school attack, Jin-woo noticed that Jin-ah struggled to maintain her normally cheery attitude ever since the attack.
(Source: Solo Leveling Wiki, edited)