Helen, alias Mother Ant, belongs to the underground-dwelling Ant Family (Ari no Ikka) located near Milk Chan's house. She is the wife of Yoshiki Arita and mother to their larval son, Ario. Helen's conduct becomes a focal point of escalating marital strife, fueling Yoshiki's deepening suspicions of her unfaithfulness. She consistently denies his accusations or shifts focus to Ario. The rising tension culminates in Helen abandoning the family home with Ario. This departure directly triggers Yoshiki's subsequent suicide in the final episode; he leaves a farewell letter for his family. Helen's actions and the resulting fracture of the ant family unit form a recurring subplot that contrasts the main narrative.