Brooke Walker, known as Umimi Habara in the Japanese version, is the wife of Mayday Walker and a Pro-Duelist appearing in the Yu-Gi-Oh! ZEXAL anime.
Her Japanese name "Umimi" means "Oceanic Beauty" while her surname "Habara" means "Feather Field". Her dub name "Brooke" means "Small Stream". Both of her given names is likely chosen because of her using ocean-themed Deck.
Brooke was a friend of Anna Kaboom and was a few years older than her. During this time, Brooke taught Anna how to Duel.
Brooke and Mayday were a couple that just got married. When she threw her flowers, Anna was the one to catch them, along with a card in the bouquet called "Devoted Love". After Anna took it out, Brooke came and told her that card will find her her true love. After the wedding, Brooke and Mayday became a pro Dueling couple.
Yu-Gi-Oh! ZEXAL II
They were invited to participate at the Heartland Academy's Fun Fair for a Couples Duel tournament. which was said to be her last Duel. When she was preparing her Deck, the lights went out and then darkness surrounded her. After a few seconds, Vector appeared and brainwashed her while giving her "Rank-Up-Magic Barian's Force" to Duel against any Number holder for the tournament. When Anna arrived, she thought that Yuma was her boyfriend. At the tournament, Brooke encountered Anna again, who was mad that she wanted to quit Dueling. Brooke tried to explain things to Anna, but they decided to settle things with a Tag-Team Duel, with Anna coercing Yuma Tsukumo into being her partner after stealing a school uniform from Tori Meadows in order to pose as a student. During the Duel, Brooke Summoned her "Unsinkable Titanica", while utilizing cards that supported her husband and eventually brought out "Skypalace Gangaridai".
When she was about to be attacked, Mayday used "Xyz Move", to protect her, which delighted her. When she drew and saw "Barian's Force", she heard Vector's voice telling her to use it. When she used it, Mayday was oblivious to how she got the card. She used it on "Gangaridia" to Special Summon "CXyz Skypalace Babylon". After giving control of "Babylon" to Mayday, she told him to use it and win no matter what, which made Mayday question it. After she was defeated, she almost fell to the ground violently before Mayday caught her. Although freed from Vector's control, Brooke somehow remembered what happened while she was brainwashed. Later that evening, she talked to Anna about the Duel and told Anna that she was just taking a break from dueling because she was pregnant (in the English version, she was taking a break to teach). When Brooke inquired about Anna finding her true love by using "Devoted Love", Anna blushed without responding. She then turned Anna around and then told her to make Yuma her boyfriend. Brooke pushed Anna towards Yuma, saying "direct attack", causing Yuma and Anna to fall down a flight of stairs.