OVA
Description
Chelsea is a princess from a magical world who arrives on Earth with a determined mission: to find a suitable husband. To accomplish this goal on a foreign planet, she secretly possesses magical girl powers, a truth she must conceal from ordinary humans. Her background reveals that she is specifically the princess of the planet Riruto (sometimes spelled Lilt), which is central to her identity and motivation.

In terms of personality, Chelsea is characterized by an intense and often comedic fixation on the main protagonist, Kazuya Watari. After he accidentally discovers her true nature, she interprets this event through the lens of her homeland's traditions, declaring him her fated husband and promptly moving into his residence. She frequently loses herself in elaborate, detailed fantasies about her future life with Kazuya, demonstrating a highly romantic and determined, if somewhat self-absorbed, disposition.

Chelsea's primary motivation is to secure Kazuya as her husband, but this quest is constantly complicated by her rivalry with the mysterious hero known as Guardian Hearts. She holds a deep and persistent grudge against this hero, blaming Guardian Hearts for repeatedly foiling her attempts to get closer to Kazuya. This frustration drives a significant portion of her actions, as she devises various schemes to lure out and confront her perceived rival. In her efforts to oppose Guardian Hearts, Chelsea often forms temporary alliances with the other supernatural girls living in Kazuya's house, such as the cosmic ninja Maya and the alien Kurusu, who share her goal of getting revenge on the hero who makes them suffer.

Chelsea's role in the story is that of a romantic rival and a comedic antagonist to the series' heroine. She is one of several extraordinary girls, including Hina and Maya, who attend the same school as Kazuya. She and her allies believe that Guardian Hearts appears whenever Kazuya becomes close with a girl, leading them to leave other girls alone with him as bait, unaware that their target is actually Hina herself. This creates a central irony, as Chelsea directs her hostility toward the alter ego of a girl who is, unbeknownst to her, her housemate and romantic competitor. A notable episode focuses specifically on her, titled "Chelsea's Magical Birthday," which highlights her importance as a character.

Regarding character development, Chelsea remains largely static throughout the series, defined by her unyielding pursuit of Kazuya and her blind hatred for Guardian Hearts. The key to her situation is her consistent failure to recognize that her rival is Hina, which preserves the comedic misunderstandings that drive many of the plots. Her key relationship is, of course, with Kazuya, the object of her affection, followed by her antagonistic relationship with Hina, whom she sees only as an occasional ally or a rival for Kazuya's attention, not as her true enemy. Her notable abilities include her magical girl powers, though the specific nature of these powers is secondary to her role as a determined and frustrated princess seeking love and revenge in a chaotic household.