Father Ant, also known as Yoshiki Arita, resides underground near Milk Chan's house as part of the Ant Family. He is Helen's husband and father to their son, Ario. Initially portrayed as overbearing and suspicious, Yoshiki's demeanor shifts as he becomes consumed by the belief that Helen is unfaithful. His escalating paranoia fuels intense rage and repeated confrontations. Helen deflects these accusations with denials or by shifting focus to Ario. This ongoing marital conflict tracks Yoshiki's progressive emotional deterioration. Despite his anger, Helen eventually leaves, taking Ario with her. Abandoned, Yoshiki writes a final letter to his family before taking his own life in the series' concluding episode. His storyline provides a darkly comedic yet tragic counter-narrative, depicting the collapse of his family unit under the weight of his uncontrollable jealousy and despair.