Lulu Takigawa, later Lulu Kirifuda, emerges as a childhood friend of Katta Kirifuda. Her early years were marked by fragility and frequent hospitalizations starting at age four. Katta provided solace through regular visits, while her brother Lucifer gifted her a pouch necklace containing the 3D Dragheart card and a promise to watch fireworks together. After Lucifer vanished, her memory of him dimmed. Raised by her grandfather, she remained unaware of her biological family until discovering a letter from her brother hinting at a reunion at the Duel Masters National Tournament. Unable to endure long duels due to her health, she resolved to have Katta compete for her.

In youth, she befriended a sushi seller and pledged to protect his shop. Following his move to America, she transformed it into a card shop, managing it with her grandfather. This shop became a hub for Katta and his team. Later, after relocating, she and her grandfather opened a bar in a shopping district popular with younger duelists, including her son Joe Kirifuda.

Her appearance features a shiny forehead, with hair typically in two pigtails. She alternated between a school uniform and an apron during work. As an adult, she wears her hair down or tied in pigtails, growing noticeably longer in later seasons.

Her personality blends affection, resolve, and concealed physical power. She openly expresses romantic feelings for Katta, bolstering his dueling through deck construction, acquiring cards like Glenmalt, Dragon Ruler, Gaiheart, and Galaxy Greatsword, and offering strategic counsel. She also manages his tournament schedule and nutrition. Despite a gentle exterior, she exhibits extraordinary strength—lifting multiple people or duel tables with ease, even hurling individuals skyward. This power continues into motherhood, evident when carrying heavy flour bags or disciplining her son Joe.

She displays vivid emotional shifts, from daydreaming about Katta to ominous expressions, and harbors a love for sweets like desserts and cakes. Though not a frequent duelist, she demonstrates considerable skill, achieving 20010 points in the Star Cup and defeating elite opponents like Kojiro Sasaki. Her dueling emphasizes precise shield management and creature control, utilizing cards such as Miracle Star, Heaven Revolutionary Knight Emperor. Her rivalry with Utsubomi Kazura escalates into fierce duels, where Kazura once burned a photograph of Lulu with Katta.

Her story intertwines with Lucifer's revelation as her brother. Reuniting after a decade rekindles their bond, mirroring Katta's relationship with his brother Shobu. During the Lucifer World Cup, his blue rose triggers fragmented memories. Later, when masked duelist Gyou attacks her and Katta, the pouch necklace reveals Lucifer's card, clarifying her childhood recollections. She duels Gyou using the card and executes techniques like 2D and 3D Dragsolution but loses and collapses.

As Joe Kirifuda's mother, she balances nurturing care with stern discipline. She retains habits like blissful journal reading but becomes flustered if interrupted. Influenced by Katta, she grows accustomed to interacting with creature spirits. Her role evolves to support Joe's adventures while maintaining the family bar.

Key developments include her participation in a 3-on-3 New Year exhibition match with Katta and Hokaben, confronting Kazura over romantic rivalry, and eventually marrying Katta. Her journey concludes with familial stability, overseeing the bar and observing the next generation of duelists.