Mina Simington, known as Mikage Sagiri in the Japanese version, is the meek secretary to Rex Goodwin who watches over Jack Atlas. Despite her dedication and loyalty, Mina tends to unintentionally spark the wrath of her superiors. Mina loves Jack and rivals Carly and Stephanie for his affections. At the same time, Trudge has a crush on Mina. Mina does not seem to get along with Lazar, as seen by them bickering while watching Jack DuelYusei Fudo (this is made more obvious in the English dub).
Mina has short, blue hair and gold-colored eyes. She appears to be wearing a white blouse under a gray-blue jacket that ends in the front abdomen above a brown belt, but falls past her white skirt in the back. Her outfit is also accompanied by brown heels and blue dangle earrings.
During the third arc of Yu-Gi-Oh! 5D's, she has longer hair and keeps her jacket unbuttoned.
Mina was assigned by Rex Goodwin to keep tabs on his protege, Jack Atlas. After Lazar reported Jack's meeting with Yusei Fudo, Mina told Goodwin about it during a meeting with Zigzix. Though Goodwin politely excused himself from the meeting, once in the hall, Goodwin chastised Mina harshly afterwards, and nearly strangled her for letting Jack anywhere near the "Satellite scum". She, Goodwin, and Lazar watch the Duel between Yusei and Jack on the police scanner, and Mina is seen casting her superiors a nervous glance.
She is also a part-time manager for Jack's Dueling career. She also encourages Jack to play as the King for the public to keep his image.
Mina took care of Jack after he was hospitalized from his Duel with Yusei Fudo during the Fortune Cup.
Mina and Trudge tracked Jack down after he left the hospital and found him staying with Carly Carmine. Mina becomes upset when Jack refuses to leave with her and jealous that he'd rather stay with Carly.
Eventually, she helps Jack get back to Satellite by helicopter, where they find Yusei Dueling Kalin. Although Jack wanted to get closer, Mina advised that he stay in the helicopter because he doesn't have his Duel Runner with him and couldn't do anything.
After Yusei and Akiza's second Duel, she informs Akiza that Sayer was using her and other Psychic Duelists to wage a war on the world that rejected them. As Akiza runs from the truth, she says it's pointless to deny this.
As Officer Trudge daydreams about being in love with Mina and giving her a flower he picked, he notices her in conversation with Jack and realizes Mina has feelings for Jack, who cares more about Carly and blames himself for her being consumed by an Earthbound Immortal.
After Yusei and Roman's Shadow Duel concludes, Mina reveals to the Signers that the Ener-D Reactor posseses four control units that were installed after the system was shutdown due to the Zero Reverse incident. Each unit has a codename which corresponds to each of the Nazca Lines, those being the Giant, Lizard, Hummingbird, and the Monkey. The Spider corresponds to the reactor itself.
She also reveals to the four Signers, that their corresponding Signer Dragon cards were designed to activate these stations. After revealing the location of the four control units, and after each Signer deduced where their acknowledged rival was waiting for them, they split up. Mina takes Akiza by car to the Lizard control tower to face Misty Tredwell. The two of them become aware of the Monkey Geoglyph on the sky as Luna faces off against the Dark Signer, Devack.
As Jack faced Carly in a Shadow Turbo Duel, she notices the Hummingbird Geoglyph in the sky. As Akiza senses it through her birthmark, she asks Mina if she is worried about Jack. Mina responds that she has faith in him and knows that there's no way he'll lose. After the Duel ends and the geoglyph disappears, Mina is relieved to hear from Akiza that Jack won.
While on the road to their destination, Akiza tells Mina about the first time she Dueled against Misty and about the fact that the female Dark Signer blamed her for Toby's death. Mina asks if any of this is true, to which Akiza responds that she doesn't remember, making the assumption that maybe Misty misunderstood something.
Finally, the two of them reach the location of the last Tower: An old and abandoned carnival. As they split up in search of Misty, Mina is soon tricked by a disguised Sayer and locked into an underground water cage. She is later joined by Yusei, who has been assaulted and trapped in the cage by Sayer. They both are saved later by a determined Trudge who, at first, couldn't open the sealed water cage. Mina cries out for Jack to help, which infuriates the jealous Trudge, giving him the strength he needs to free them. As they notice the Lizard geoglyph on the sky, Yusei soon hurries to where the Duel is taking place. He is stopped as Mina tells him about the reason for Misty's planned revenge against Akiza. After he leaves, Mina and Trudge also get to the Dueling site, where both Leo and Luna are watching, too.
After the Duel ends in Akiza's favor, they all see the appearance of the King of the Netherworld, who is heading towards the newly formed Condor geoglyph in New Domino City. The Crimson Dragon appears once again and guides everyone to Rex Goodwin's mansion, where Goodwin reveals to them his identity as the both the Fifth Signer and the final Dark Signer, and then declares that a Shadow Turbo Duel will be held within Condor geoglyph as a ritual to welcome the King of the Netherworld.
As Yusei, Jack, and Crow accept the Duel in order to stop the resurrection of the Underworld Ruler, Mina along with Trudge, Leo, Luna and Akiza are currently watching.
Once Yusei finally defeats Goodwin, everything returns to normal and everyone resumes their normal lives. After that, Akiza, Leo, Luna, and Mina sit at a table looking at Misty Tredwell's latest pictures. As Leo mentions that Yusei is late, Trudge pulls up, noting that Jack and Crow haven't shown up either. Carly, disguised as an old man, reveals herself and is shocked that the two haven't shown up, thinking there could be a scoop. Trudge asks her if she already has a scoop but Carly remarks that no one remembers anything and she doesn't remember anything before she became a Dark Signer. Akiza smiles, thankful that everyone in New Domino City and the Satellite has returned.
Mina occupies another job in which she is chief of Special Investigations, with Trudge serving as her assistant. They are the ones looking into the Ghost situation and also ask for Yusei, Jack and Crow's help to resolve it. After the Duel against Ghost and its identity being revealed as a Duelbot, Mina reveals that the robot is a prototype.
When Yusei later goes missing, she accompanies Akiza on her search.
A while afterwards, she, along with Trudge, takes Yusei, Jack, and Crow to a fancy restaurant in New Domino City to persuade them to take in an amnesiac Bruno.
Mina and Trudge also investigated the Jack Atlas case when he accused of forcing opponents into a Turbo Duel with the intention of making them crash. Mina, however, appeared to struggle with the idea that Jack was responsible for the crimes he was accused of.
She got upset when Trudge displayed some attraction towards Sherry and stepped on his foot with her heel.
Mina is often seen in the stands during the WRGP , sitting alongside Trudge and her main love rivals for Jack, Carly and Stephanie . She, along with the other girls cheer for Jack a lot, and often rush to his side when Jack is in a critical condition, such as when Jack was defeated by Andre and Jakob .
After the conclusion of the WRGP with Team 5D's becoming the champions, she is seen ordering the people of New Domino City to evacuate at once during the Duel between Yusei and Z-ONE . She is seen cheering for Yusei during this Duel, clearly happy whenever he pulls off a unique move that surprises Z-ONE and when Yusei wins the Duel.
After this Duel, she is seen cheering up Carly and Stephanie after Jack makes a decision to leave New Domino City and become the World King.
Mina attends the G1 Grand Prix, where she, Goodwin, Jack and Lazar watch the tournament from their box room.
During Yusei's Duel with Greiger, Mina looks up information on Greiger and finds that he is the Mid-American Champion and known as the "Undefeated Giant". Jack smirks, pointing out that "undefeated" isn't exactly true and Mina apologizes.