Katia wears a dark green, lilac and white medium length dress with a light pink jacket. Katia has lilac shoes with darker purple heels. Katia wears a necklace that was given to her by her grandmother Sophia. She greatly resembles Sophia, but her eyes seem to come from her grandfather.
Katia is a sweet and kind girl. All of Dropstone regards her highly, and she has many friends. Her mother's premature death had an effect on her life, since Sophia essentially took her mother's place, so she was devastated when she died. She was quite close with her father, but they drifted apart in the year following Sophia's death.
While Professor Layton and Luke are investigating Dropstone, they discover that Mr. Anderson and his daughter were having some fights recently. Upon speaking to Mr. Anderson, Layton finds out that the country village of Dropstone was founded by a woman named Sophia, who was also the mother-in-law to Mr. Anderson and grandmother to Katia. They find out that Sophia had also searched high and low for the Elysian Box. Upon boarding the Molentary Express to leave Dropstone, Layton and Luke witness a large crowd of people, who appear to be seeing someone off. That someone being Miss Katia Anderson.
They reboard the train and eventually find themselves in the deluxe car of the Molentary Express. Here, the number two car of the train switches with another train's while the Express was in a shadowy tunnel. Upon waking up, Layton and Luke discover a dark and misty sky and the train finds its way to the mysterious phantom town of Folsense. While searching through Folsense, Layton and Luke find Katia many times and try to interrogate her about the Elysian Box. However, their efforts become fruitless. Katia is also met up with Inspector Chelmey and he begins to interrogate her. After a long time in Folsense, eventually all meet up in the hotel to discuss Dr. Schrader's death. After foiling Don Paolo's plans, Layton obtained the Elysian Box. Katia wanted to return the box to who really should have it, but Layton still keeps the box. He opens it, but there was nothing inside...
After opening the Elysian Box and finding nothing of use, Layton figured it was time to give the so-called vampire in Herzen Castle a visit. During their time in the castle, they met Katia. After escaping the clutches of Anton and making their way into the Great Room, Anton catches them again and sees Katia. He starts acting strange, believing that Katia is his long lost love, Sophia. He asks her to come closer, but Katia hides behind Layton. Anton laughs at the notion of Layton being the reason Sophia left him and challenges him to a duel. Layton grabs the correct sword on the wall and two do battle. After battling each other and making it to the top of the room, Anton tires himself out. Katia yells, telling him to stop. In doing so, she tells him that she is his granddaughter, but Anton thinks this can't be true as he thinks he's too young to be a grandfather.
Katia and Layton explain to him what has happened to Folsense over the course of 50 long years. Katia explains that Sophia had never betrayed him; she left Folsense because she was pregnant, and couldn't bear endangering their child. Katia ends this talk by saying that Sophia never stopped loving Anton, even until she died. Upon realizing that Sophia is dead, Anton begins to swing his sword maddeningly, cutting a chain, holding up the chandelier in the room. The chandelier falls and crushes the majority of the castle with it. After they escape the crumbling castle, Layton returns and Elysian Box to Anton and with the help of Luke, they open the box's secret compartment. Inside was a letter, but not the letter Anton wrote. Instead, a reply to Anton from Sophia was inside. Sophia told him of what her last days were like and how she never left a though of him out of her mind. She told him of the tragic loss of their daughter, but ended saying that Katia was who she now wanted Anton to meet for himself. After Layton and Luke reboard the train, Anton and Katia remain in Folsense. It is unknown if Katia ever made up with her father, but it is believed she did.