

She tells Violet about how her parents died in the war and how her brother feels guilty over failing to protect them.

Luculia later meets Violet, offering to ghostwrite a letter to Gilbert, but Violet cannot find the words to say. The next day, Violet and Luculia are assigned to practice their actual ghostwriting skills on each other. Luculia meets and befriends Violet Evergarden when she begins attending the Auto Memories Doll Training School.

However, Spencer blamed himself for the deaths of their parents, and fell into depression and alcoholism, after which Luculia began taking care of Spencer. After the war ended, Spencer came back alive, which was more than enough to make Luculia happy despite their parents' deaths. However, one day when Luculia's parents went to a town for business, the Western Front was broken through, and her parents were killed in the fighting. However, there wasn't much fighting on the Western Front where Spencer was located, so Luculia claims that the war didn't feel real to them. When the war began, Spencer was drafted into the army. Luculia had a normal yet very peaceful childhood with her parents and older brother, Spencer Marlborough. She always looks to assist others in any way she can and can be described as selfless. She is expressive and sociable, but she struggles to communicate her own feelings, particularly regarding her brother. Despite a tragic backstory, she is shown to carry a positive attitude and cheerful demeanor when around other people, but tends to be more quiet and solemn when alone. Luculia is constructed as a kind and considerate person who is willing to go out of her way to assist others, shown by events such as her offering Violet Evergarden some of her food the first day they met or attempting to help her write a letter to Gilbert Bougainvillea. After becoming a Doll, she wears her hair in a high ponytail with a golden band.

She also styles her hair by wearing a braided headband. She has long, straight scarlet-red hair, which falls down to her lower back, with two locks of hair framing her face on each side. Luculia is a fair-skinned young woman of medium height with freckles and olive green eyes.
