Mary Buttman is the mother of Abel and Arthur Buttman in the anime Lady Georgie. After the death of her husband Eric, she takes on the responsibility of managing the family farm and raising her two sons alone. She is a woman driven by anxiety and deep-seated fear, particularly concerning her adopted daughter Georgie. Her primary motivation stems from her worry that her sons have begun to see Georgie as a woman rather than a sister, which leads her to treat Georgie with coldness and distance. She struggles to accept Georgie into the family from the beginning, both because of the girl's obscure origins as the child of convicts and because of her fear that Georgie will create rivalry between Abel and Arthur.

Mary's role in the story is that of a conflicted maternal figure whose internal turmoil and resentment create tension within the household. Her cold treatment of Georgie intensifies after Eric dies from internal bleeding sustained while rescuing Georgie from a river accident, as Mary quietly blames Georgie for her husband's death. Despite her harshness, she experiences regret over her behavior. When she discovers that Georgie has been secretly meeting her love Lowell and that her sons have come to blows over their feelings for Georgie, Mary lashes out in desperation, revealing to Georgie that she is the daughter of a convict and driving her from the home. Immediately afterward, Mary is overcome by guilt, realizing that her own bitterness has destroyed her family. She collapses from anxiety and dies while Arthur is caring for her, passing away from a broken heart over losing her children.

In terms of key relationships, Mary's bond with Georgie is strained and fraught with resentment, in contrast to the deep affection her sons feel for their adopted sister. Her relationship with Arthur is marked by his loyalty to her, as he remains by her side when Abel and Georgie leave, and he is present during her final moments. Abel's departure also contributes to her despair. Mary has no notable abilities beyond her capacity to manage the farm single-handedly after being widowed, and her development follows a trajectory from cold resentment toward Georgie to profound regret and self-awareness, though she does not live long enough to reconcile. Her character is defined by her anxieties, her inability to fully accept Georgie, and the tragic consequences of her own actions.