Martha

Martha was the caretaker of Yusei Fudo, Jack Atlas,and Crow when they were young. She seems to be regarded as a parental figure by all abandoned children in Satellite.

Dark Signers
After Yusei Fudo sustains an injury from his Duel with Kalin Kessler, Crow takes him to Martha's refuge, so that he could receive the required surgery. As the gang are waiting outside for the operation to be over, Martha assists as a nurse to the doctor, who works on Yusei.

After Yusei wakes up, Martha scolds him for growing up as an adult, just so he could forget about his foster parents, as well as beginning the task of building his first Duel Runner. All of that,just so that he can put his life in danger by going to the B.A.D Area (to stop the Dark Signers as we all know, without the help of his fellow Signers). She also tells him that she can't understand why he didn't ask for help from his friends, when Yusei's ideals happen to be "believing in friendship". Even so, she reminds Yusei that no matter what he does, he can always count on his friends that they will be there supporting and backing him up.

She's present when Akiza's father Hideo, goes to Satellite in order to ask for his help. However Yusei refuses to help as doubting that he really can do something for her. Martha figures out why as she says to him that his heart is all closed up now. This is due to the duel against his old friend Kalin, as it left him with the fear of having to face against another friend. Martha tells Yusei that now the only ones who can help him are his friends. But in order for Yusei's heart to open again, he needs to face Akiza again as a friend. Before they leave, Martha teases Yusei, saying that "seeing that he likes Akiza, Yusei better go so that he can also get his future wife".Yusei tries to reject that opinion, but agrees to help nonetheless.

Later on,when all 4 Signers along with Leo, Trudge and Mina go back to Satellite they are greeted by Martha. She seems happy that Jack is finally back too, however the reunion is cut close as Yusei finds out that Rally and the others along with Crow have disappeared. Martha then notices that Akiza is there as well, meaning that Yusei was able to open her closed heart after all. Thus as everyone is later sited on the table and having supper, Rudger suddenly appears in order to duel.

After Yusei has accepted to duel, he's accompanied by Akiza, while Jack and the rest takes Martha and the kids to safer place. However as 3 of the children, Takya, Jun and Michan, have decided to watch the duel; Martha notices this and along with Trudge are gone looking for them to where Rudger and Yusei's duel is taking place.

As his Spider geoglyph has formed on that area, she and Trudge eventually get near the dueling site but away form the Nazca Line. As she notices Yusei they both then see Juna and Michan who are scare and there inside the spider geoglyph no less. Just then they hear Akiza who says to them that an Earthbound Immortal is about to be summoned, and that the kid's soul will be sacrificed. Martha worried now because of this tells Yusei to protect them, however with help from Jack and Trudge, Martha manages to save the children when "Earthbound Immortal - Uru" is summoned. She manages to get Takya to Trudge, but falls into the geoglyph and is sacrificed into Uru.

After Yusei and everyone else returns to her home, the children try to apologize for the occurring incident to Dr. Schmitt stating that its their fault for what happened to her. However Yusei states that it isnt and that the true culprits to blame are the Dark Signers. He then makes them believe that once the Dark Signers are defeated, than then Martha and everyone else will return back.

After Yusei and Rudger's second duel ends, she finally returns along with Rally, Tank, Nervin, Blitz and other people sacrificed to summon Uru.

Third arc
Yusei, Jack and Crow have gone back to Martha's home, long after the events with the Dark Signers have passed. In here she and Schmitt tell them about a stubborn man named Tetsuzo who refuses to leave its home. Since he leaves there alone there worried something could happen to him, as his property is one big junkyard.

As they can't figure what to do about the situation, the children then trick Crow into finding a solution. And after he duels Tetsuko and learn the reason behind his refusal to leave its house, involving a son he had. Yusei, Jack, Crow and Blister are able to convince him to leave, by telling him that in Martha's home there exists other kids that could surely be his grandchildren. Once Tetsuzo moves in there, he even builds a statue made out of junk in front of her home. Thus the statue itself has been made in the form of Yusei's, Stardust Dragon.