Martha

Martha is a caretaker of Yusei Fudo and Crow when they are young.

After Yusei Fudo sustains an injury from his Duel with Kyosuke Kiryu, 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 asists as a nurse to the doctor, who works on Yusei.

After Yusei wakes up Martha scolds him for growing up to an adult, just so that he forget about his foster parents as well as begginnig the task of building his first Duel Runner. All of that just so that he can put life in danger by going to the B.A.D Area(to stop the Dark Signer]s] as we all know, without the help of his fellow [[Signers). She also tells him that she can't understand why doesn't he didnt' ask for help with his friends, when Yusei ideals happen to be "believing in friendship".

Even so she reminds Yusei that no matter what he does, he can always count with his friends that will be there supporting and backing him up.