Lucia is a well-endowed, beautiful woman with dark blue hair and yellow green eyes. Very similar to those of her daughter, Elise. She wears a white buttoned shirt covered by a vest. Along her waist is a white apron. She uses a golden shawl to drape herself with whenever she goes outside or if it gets too cold.
She is a loving wife and a devoted mother who really cares for the well being of her family. Towards Elise, Lucia is strict and always encourages her to be the best she can be and to always look forward. However, she is more doting and gentle towards Rean. Despite his situation, she comforts him and lets him know that she is always there for her son. To her husband, she is always by his side, helping him make important decisions and consoles him when things are looking bleak.
While being adverse to violence, she is willing to take up arms to defend her home and loved ones if either are threatened. The people of Ymir refer to her as a kind woman and is held in high regard, along with her husband.
Lucia is seen for the first time when she welcomes Rean back to Ymir during the October War. She is concerned for the robustness of the festival, thinking about traditions that have been lost. She states that she will support Rean, no matter what he decides to do.
When the village is attacked, Lucia implores the princess Alfin to get to safety. She takes care of tending to her husband when he is injured in an attack, although she thanks Sharon Kreuger for being there to help her with housework.
Lucia and her husband Teo briefly talk with Rean over the phone reassured that he and Elise are fine after their disappearance following the Great Twilight. They are not worried so much about Ymir as Giliath Osborne has promised not to involve it.
Lucia looks after the Bright family during their stay in Ymir. They warn her about the boar monster wandering around and she tells them that they will keep a look out. She later reports that she can hear a battle with the boar in the near distance. Lucia remarks that the Brights are an 'unusual family'.
Lucia and Teo return when Rean and his class arrive in Ymir, awaiting him in the study. They greet him after six months apart, as well as the class and Claire Rieveldt. She then has lunch prepared for everyone. Lucia remarks the Schwarzers and Royal family have always been close, but didn't want to foster that onto the next generation, but she states Alfin and Elise became close of their own accord.
Lucia later hears the roar of a Magic Knight, but leave it in the hands of Rean and his class, believing in them.
She expresses shock at the news of Olivert going missing. Afterwards, Musse tries to obtain information about Rean's childhood from her, along with any other personal details as she helps with the housework.
- Her name, Lucia, is the feminine form of the name "Lucius", which means "light".