Li

Based on what we have seen, Li is a protective (probably because of her job, or because she has a crush) person, especially towards Noah. When Parish was being rude to her, she was able to retaliate, and stated; "I work for Noah, not you." (not exact words). She has a good relationship with Noah, often speaking her mind.

In the past/other timeline, Li had died/sacrificed herself. From what we saw on the image, she was suffering from a neck wound, and had died over the wound.

Personality
Li seems to be very calm, even if everyone else is in a panic. She also is quite respectful to those she cares about, such as Noah.

Appearance
Li has short brown hair that falls just above her shoulders, along with a fairly tall structure. Throughout the webtoon, she is shown to change clothes quite often. Every outfit (except the maid outfit) includes pants with a simple top, and occasionally a jacket.

Abilities
Li is shown to have an ability to manipulate ice. However, from what is shown, she cannot control it properly. It appears to be quite strong, but seems rely solely on her emotions. In the other timeline, however, Li was one of the first to use her power and had far more control over it.

She is shown to be a great sharpshooter and martial artist, due to her past training at a facility.

Background
For the duration of about two and a half chapters, we can see that Li used to live on the streets, stealing with another group to survive. However she, along with another child whom she cared a lot about, were moved to a training facility. Here, her full skills were shown, and she became one of the top students here. Sometime around, she met Noah, who helped her and her friend get out of a nasty situation.

Noah Collins
Li greatly respects Noah Collins, seemingly because of her past.

Neo Collins
She seems to listen to Neo, due to the fact that he is the son of her master. She also seems to be quite kind to him, unlike how she somewhat treated Parish, Neo's mother.

Parrish Collins
Since Parrish is Noah's wife, Li acts respectful to her, but doesn't necessarily like her. She shows contempt and slight disgust for Parrish on many occasions because she knows how much pain Noah has gone through because of her.

Trivia

 * In Chinese origin the name Li has a meaning of "logic, dawn, strength, beautiful, and upright"(could also be pear)