Wreathlit Noel, known as Wreath, hails from the Moon, appearing as a petite blonde girl with green eyes despite her advanced true age. She stands 139.2 cm tall with measurements of B63/W49/H67, typically dressed in a kemonomimi-style hat and dress that accentuate her reserved, antisocial nature. Though she rarely speaks or engages socially, she frequents Trattoria Samon and shows distinct affection for Sayaka, while Tatsuya's dogs exhibit unusual fondness toward her.

Her existence serves as a vessel for Fiacca Marguerite, a scientist from the Oedipus War 500–700 years prior. Fiacca emerges as a split personality, embodying historical Earth-Moon tensions and insisting on their separation. This duality fuels internal conflict when Wreath develops feelings for Tatsuya Asagiri, with Fiacca's presence visually marked by crimson eyes during antagonistic episodes.

During Feena Fam Earthlight's storyline, Wreath covertly observes the princess's bond with Tatsuya. Fiacca actively sabotages their relationship to thwart Earth-Moon unity, but witnessing Tatsuya and Feena's unwavering commitment to peace—and their success in resolving ancient conflicts—compels Fiacca to relinquish her opposition. She departs permanently, breaking the cycle of hatred and freeing Wreath from internal division.

In the *Moonlight Cradle* sequel, Wreathlit Noel's ties to Fiacca deepen through Cynthia Marguerite, Fiacca's younger sister. Preserved via time-dilation technology, Cynthia unveils further layers of Fiacca's historical actions and relationships.