TV-Series
Description
Jonathan is a baby seal who becomes a resident and performer at the Kaleido Stage. His background begins when the main character, Sora Naegino, discovers him resting on a beach after accidentally tripping over him. Sora secretly brings him to her dormitory at the Kaleido Stage, as a policy against keeping pets was in place. After his presence is revealed when he startles another performer, Layla Hamilton, Sora works to raise funds for his food by taking a part-time job and entering a juggling contest. Following Sora's persuasion, the owner Kalos Eido agrees to let Jonathan stay permanently, and a stagehand, Jake Benigni, constructs a special tank for him.

In terms of personality, Jonathan expresses himself through simple barks and is portrayed as a funny and highly intelligent creature capable of understanding human emotions. He possesses a playful nature, often finding himself at the heart of light-hearted moments, and can display a stubborn streak, particularly when it comes to performance partnerships.

Jonathan's primary motivation appears to be companionship and performance. His role in the story is that of a unique member of the Kaleido Stage troupe. He is not merely a pet but an active participant in shows, often performing tricks and comedic acts that are particularly popular with younger audiences. At times, his coordination in these performances surpasses that of the human performers, leading to humorous situations. He also has the unique distinction of being one of the few characters who can see the spirit of the Kaleido Stage, Fool, although this occurs under comical circumstances.

Jonathan's key relationships evolve over the course of the series. He is initially befriended and cared for by Sora Naegino, who becomes his first partner for outdoor shows. He also forms a strong bond with the young stagehand Marion Benigni, frequently seen riding atop her head. This relationship deepens in the second season, during which Jonathan decides to perform exclusively with Marion on the Kids Stage, developing his own distinct personality and refusing to work with anyone else. His other friends include performers Anna Heart, Mia Guillem, and Rosetta Passel.

Throughout his development, Jonathan transitions from a secret, hidden pet to an official mascot and performer at the Kaleido Stage. His most significant change occurs across the seasons, as he grows less dependent on Sora and becomes a dedicated partner to Marion, showcasing a more independent and selective personality. He also appears in original video animations, including one where he and Marion attempt to teach the seal language to Sora.

Jonathan's notable abilities include a talent for performing tricks and juggling, often with surprising skill and coordination. He can understand human communication and intentions, making him a capable scene partner in comedic acts. Beyond the main series, he demonstrates a form of communication in the OVA "Good da yo! Goood!!," where he is featured in a segment educating about seal facts and language. He also contributes to the franchise's music with a duet song titled "M&J" performed with Marion.