Luka Millfy/Gokai Yellow as described by Wikipedia is a tomboyish girl and the ship’s lookout.
Gokaiger Episode 6 is entitled, The Most Important Thing. You’ll find Luka’s screencaps below. Here’s the summary:
Luka goes shopping for jewelry with Don when they encounter a tycoon named Kozo Kasugai and his spoiled daughter Komaki. After an argument over Komaki buying the entire jewelry store, Kozo offers Luka a job as a maid so she can buy the ring she wants. At the mansion, he shows her all of the priceless antiques on display, including his most prized, heavily-guarded possession: a gold tree. However, he assigns her not to guard it, but to look after Komaki. While cleaning Komaki’s room, Luka sees a worn, tattered rabbit doll and throws it in the waste basket; this infuriates Komaki, who kicks her out of the room.
Later, Luka tells the Gokaigers about the Kasugais and their unusual attitude toward money. The Gokaigers discover that a few years ago, an impoverished Kozo discovered a strange meteorite that fell on Earth and changed into a tree that bears gold instead of fruits. Meanwhile, the Zangyack Empire sends Action Commander Nanonanoda to Earth to steal the gold tree.
Nanonanoda enters the mansion, but is quickly caught by Luka and Komaki, causing him to be zapped out of the gold tree’s room by the security lasers. Outside the mansion, Luka makes a deal with Kozo to get rid of Nanonanoda for a large sum. She changes into Gokai Yellow before using the Ranger Keys of Vul Panther and Bouken Yellow before throwing the Zangyack Action Commander out of the premises. Kozo rushes to upgrade the gold tree room’s security system, not caring about his daughter’s safety.
Later, Luka confronts Komaki on why she did not alert her father on the intrusion. Komaki tells her she and her father would be better off without the gold tree. Before Kozo discovered the meteorite, he was a poor man struggling to make ends meet and keep his daughter happy; the cheap rabbit doll was a birthday gift for her made by him. Luka then lectures Komaki that money makes the world go round. Back aboard the Gokai Galleon, as she throws darts at a drawing of Komaki, Luka looks back at her past as a homeless girl giving bread to other impoverished children. She and Joe talk about how she needs money to fulfill a life-long dream.
The next morning, Nanonanoda invades the mansion with a platoon of Gormin, setting the complex on fire. The Gokaigers intervene, with Luka rushing to save the Kasugais while the rest deal with the invaders. Luka finds the father and daughter and tells them to leave the burning mansion immediately, but Komaki hesitates – saying she does not want to leave something important. Kozo then signs a check for 10 million yen and has Luka retrieve the gold tree. Luka then tells Komaki she will bring back the prized possession.
As the Kasugais leave, Luka changes into Go Yellow to extinguish the fire around her. Meanwhile, the other four Gokaigers change into J.A.K.Q. Dengekitai and quickly dispatch the Gormin before battering Nanonanoda with the J.A.K.Q. Hurricane. Luka escapes from the burning mansion, having retrieved not the gold tree, but Komaki’s rabbit doll. Kozo discovers that his daughter has held onto it for a long time and realizes that his wealth had distanced him away from her. As the gold tree melts from the fire, Kozo apologizes to his daughter and agrees with her to start over again.
Not being good at situations like this, Luka changes into Yellow Racerand leaves the scene to regroup with the Gokaigers and eliminate Nanonanoda with the Final Wave. When Insarn revives and grows Nanonanoda, Gokaioh is summoned to destroy the Action Commander with the Gokai Full Burst. As the Kasugais watch the battle, Komaki discovers that Luka returned the check inside the doll. Later, the Gokaigers commend Luka for her generosity toward the Kasugais, with Joe mentioning that she practically worked for free. Luka then reveals to them the ring she wanted earlier in the episode. She explains to them that she had a little bit of free time during the fire.