Cleao Everlasting is a central character in the anime Orphen, serving as the primary female lead and a key companion to the protagonist. She is the youngest daughter of the wealthy and noble Everlasting family, residing in the city of Totokanta. Her early life was one of relative shelter and privilege, though she was also plagued by illness as a child, at one point being bedridden for an extended period and requiring surgery that left a scar. Perhaps in response to this protected upbringing, she developed a restless spirit and a powerful yearning for travel and adventure beyond the confines of her home.

Physically, Cleao is a teenage girl with fair skin, long blonde hair, and pale blue eyes. Her most distinctive features are her disheveled bangs with two signature twirls of hair on each side of her head. Her fashion changes across adaptations, ranging from a long blue dress to more practical traveling attire like an orange dress or a white shirt with jeans. She is notably athletic and agile, standing 155 centimeters tall with a lean build. Her name is also spelled Claiomh Everlasting in some sources.

In terms of personality, Cleao initially comes across as a carefree, headstrong, and somewhat bratty girl who has been sheltered from much of the world. She is confident in her own abilities, outgoing, and possesses a mischievous streak, enjoying teasing others and rarely liking to admit when she is wrong. This trait frequently causes her personality to clash with Orphen, leading to many arguments and silly fights. However, beneath this feisty exterior lies a very brave and kind-hearted individual. She possesses an unusual and genuine interest in sorcery, which is notable given her noble upbringing. Rather than fearing the mystical arts, she is drawn to them and shows great courage when facing magical threats.

Her primary motivation is to leave her sheltered life behind and see the world, experiencing the thrill of adventure and fighting alongside her companions. A deeper, more personal motivation is her desire to become a successful and reliable partner to Orphen. She wants him to see her as an equal and to feel comfortable turning to her for help, which creates internal conflict when his independent nature prevents him from doing so. This desire is driven by a mixture of admiration for Orphen and a personal struggle with feeling like a burden, especially since she is the only member of their traveling group who cannot use sorcery. This insecurity makes her determined to prove her worth and contribute in any way she can.

Cleao plays a significant role in the story as the catalyst for the journey. Her father came into possession of the Sword of Baltanders, a magical artifact that Orphen needs for his quest. Orphen takes the sword, but Cleao insists on accompanying him, initially claiming she must protect her investment. This arrangement serves as the flimsy pretext for her to join Orphen and his apprentice, Majic Lin, on their dangerous travels. Throughout the series, she acts as the group's heart and a source of grounded, determined energy, often pushing forward with courage when situations become desperate.

Key relationships define much of her development. Her central relationship is with Orphen. What begins as hero-worship and a clash of wills gradually deepens into genuine affection and mutual respect. While she often treats him as a nuisance, she also looks up to him and respects his abilities. Over time, Orphen becomes deeply attached to her, and by the conclusion of the original novels, they have married and have a daughter named Ratsbane. She also forms a close bond with Majic Lin, whom she often teases and uses as a test subject for pranks she intends to try on Orphen. Another pivotal relationship is with Leki, a small, puppy-like Deep Dragon child she discovers in the Fenrir Forest. During a confrontation with Leki's mother, the powerful dragon Asraliel, Cleao's courage and angry outburst lead Leki to turn on the other dragons, securing his loyalty as her companion. Leki remains by her side, becoming her familiar and a crucial source of support. Her relationship with Mädchen Amick is also notable. Despite an initial contentious meeting where she found Mädchen pushy and dismissive, Cleao later risked her life to save her, destroying a celestial doll that had imprisoned Mädchen and earning her eternal loyalty.

Cleao undergoes significant development over the course of the story. She evolves from a somewhat selfish and sheltered noble girl into a resilient and capable adventurer. Her journey forces her to confront her own insecurities about not being a sorcerer and to discover her own unique strengths. Her bravery is repeatedly tested, and she proves herself invaluable not through magical power, but through her quick thinking, athleticism, and unwavering determination to protect her friends. A major turning point is the unlocking of her latent magical potential, which is revealed to be considerable. She unconsciously channels this power through Leki as a medium, and by merging her mind with his, she is able to access and train her abilities. She eventually receives formal training from Leticia McLady, completing her development as a sorcerer.

In terms of abilities, Cleao is an athletic and skilled fencer, having taken sword fighting lessons as part of a war club during her school years. While her technique is initially unrefined, she has natural talent and surprising strength, demonstrated by her ability to hold her own in single combat against trained fighters like Hartia and even topple a golem with a powerful kick. Her primary weapon for much of her journey is the magical Sword of Baltanders. Later, it is revealed that she possesses a high, uncanny level of latent magical capacity. She lacks formal training, so she initially channels this magic unconsciously through her bond with Leki. Once this power is unlocked and she receives instruction from Leticia, she becomes a capable sorcerer in her own right, further developing her skills over time.