She is fair, upright, amiable, warm-hearted, and symbolised by life, and the Cleric class. Always friendly and positive, Yustiel is loved and respected by all the inhabitants of Elysea. She has a gentle, caring nature, and craves peace above all else. This often puts her at odds with Kaisinel.
Yustiel stays in Elysea out of obedience and faithfulness to Ariel, but she cares not where her home is. Her only wish is to end the war and go back to the time of ancient Atreia.
Later we learn that she is trying to save Eltnen from the rapid desertification that threatens the region, and thus the disappearance of Aether this entails. To this end she invented special fountains called the Mystic Springs that gush forth an endless amount of water if powered by a magical artifact known as Life Stone, and planted several of them in the region. She was able to stop the further ruin of Eltnen, but the Lepharists have recently been trying to destroy these springs or poison the water. Ultimately she wants to bring back Eltnen's former glory as the breadbasket of Elysea.
It was also another artifact created by her that allowed the player to remove the locate and remove the source of the contamination behind Verteron.
- One of her Mystic Springs can also be seen at the Observatory Village in Theobomos.
- In the Eltnen campaign it is mentioned that the Manduri inhabiting the Manduri Forest area were originally human, but that Yustiel cursed them to spend eternity as beasts after they neglected their duties. 
- In an earlier artwork commissioned by NCsoft she is depicted as a tall, slender woman with a youthful but beautiful face and long blonde hair.