Marion, daughter of set designer Jean and the late Cynthia—a trampoline artist who perished mid-performance after Marion pleaded with her ill mother to skip the fatal show—initially opposes others using the trampolines, channeling her unresolved grief into resentment toward Sora Naegino. She views Sora’s efforts as a disrespectful challenge to Cynthia’s unmatched legacy. This stance softens as Marion notices parallels between Sora’s drive and her mother’s passion, forging a bond that evolves into steadfast support.

Her healing journey intertwines with caring for Jonathan, a baby seal she and Jean nurture. Their playful companionship, symbolized by his habit of perching on her head, inspires the song “M&J,” celebrating their friendship. When Jean reveals Cynthia’s journal—containing plans for a mother-daughter trampoline act—Marion confronts her fears, embracing her mother’s craft on the Children’s Stage. A joint performance with Sora culminates in a vision of Cynthia, affirming Marion’s acceptance of her legacy.

The OVA *Good dayo! Goood!!* showcases Marion’s humor as she and Jonathan comically tutor Sora in seal communication, leading to a trampoline-assisted juggling act that delights audiences. Her relationships anchor her growth: Jean transitions from a figure of protective concern to a partner in honoring Cynthia, while Sora remains a trusted ally in both artistry and emotional resilience. Jonathan’s presence underscores her capacity for joy and connection, reflecting her progression from grief-stricken isolation to communal belonging.