This is a list of characters in Twin Princess of Wonder Planet.

Sunny Kingdom

Age: 8 (1st series), 9 (2nd series) Fine is one of the main protagonists of the series and one of the twin princesses of the Sun Kingdom. She has red hair and eyes inherited from her mother. Fine is called one of the "least princess-like princesses in the history of Fushigi-boshi". She has a sweet tooth for food, especially cake, despite her terrible cooking skills. She often complains whenever she sees or hears something supernatural because she dislikes horror. She and Rein are the two who help each other the most. Fine is athletic but is not a good dancer. She is friendly and tries to be happy in every situation. Fine is very naive but is always the type to help her friends, making Noche fall in love with her. She tries to cheer people up despite not knowing the whole situation and does not often express herself, trying to ignore the feelings she is hiding. Fine can understand what Shade's little sister, Milky, is saying because they both love to eat. Fine is the first to trust Eclipse (Shade) and slowly falls in love with him. She never truly knew that Shade was in love with Rein or how much Bright loved her. Likewise, she never realized that Noche was in love with her. She has shown some jealousy in situations where Shade paid more attention to Rein, such as when he saved her rather than Fine. Her favorite color is red/pink and she is still in love with Shade in the second season. In the manga and anime, she falls in love with Shade, but he is in love with her twin, Rein.

Age: 8 (1st series), 9 (2nd series) Rein is the other main protagonist of the series and the other twin princess of the Sun Kingdom. She has sea-green eyes and blue hair, inherited from her father. Although Rein is also called one of the "least princess-like princesses in the history of Fushigi-boshi," she enjoys dressing elegantly and wearing elaborate decorations. Rein becomes eccentric when it comes to romance and helps anyone in need. She is also a terrible cook, like Fine. Although Rein likes Bright, she had no idea that Eclipse/Shade had a crush on her. But Rein realized that Bright cared more about Fine than she did before. She gets seriously jealous when Prince Bright pays more attention to Fine (her twin sister). She also never realized that Fango had a crush on her, like Noche did on his twin sister. One of her main characteristics is that she is a big dreamer, fantasizing about her romance with Bright. She is adventurous, but also friendly, eccentric, and caring, which made Fango fall in love with her. Rein often thinks of positive and intelligent ways to solve things, which is why Fine depends on Rein for her ideas. She is also good at solving other people's problems and becomes a reporter for the Royal Wonder Academy. Her favorite color is blue. In the anime, she becomes Shade's main love interest. In the manga, as in the anime, Shade maintains his love interest and suggests that Rein is waiting for her to reciprocate his feelings. Her theme color is blue.

A fairy-like creature to which Fine and Rein treats as their pet. He also ends his sentences with "pumo". Poomo helps Fine and Rein on their mission to save their planet. He is also shown to have many abilities such as cooking, sewing and piloting. He almost died at the end of the first season but the last Grace stone and Princess Grace saved him, allowing him to live with Fine and Rein forever. He is also smitten by the Ballerina in the anime.

Grace is the legendary princess who once saved Fushigi-boshi in the ancient days. Although she died ages ago, she appears as an astral body inside the core of the Sun's blessing before she entrusts Fine and Rein in a mission to save the planet.

Camelot is one of Fine and Rein's maids. She can be very bossy in the beginning of the series, but has a caring and enthusiastic side to educate Fine and Rein to become more proper and decent princesses.

Lulu is a cat who serves as Camelot's trainee. She gives suggestions to Camelot in some cases and writes down comprehensive notes of Camelot's work. Lulu appears for the first time in the 11th episode.

Elsa is the queen of Sunny Kingdom and Fine and Rein's mother. She has a gentle and kind character. Fine and Rein admire her mostly because of the precious décors she made. Her hair and eyes are red (to which Fine inherited). She also cherishes the presents Fine and Rein gave her.

Truth is the king of Sunny Kingdom and Fine and Rein's father. His eyes are sea-green and his hair is blue (to which Rein inherited). It is revealed that he gave Dream Seed flowers to Elsa when he proposed to her. He is also very protective of Rein, as Fango pursues her.

Omendo is the laboratory scientist of Sunny Kingdom. He analyzes all of the climate data that are processed by the weather stations. He is childhood friends with Camelot.

Tabi and Jill are some of the workers of the weather station. In the 4th episode, Fine and Rein help Tabby out because of his overwork while Jill is very worried about him.

Moon Kingdom

Shade is the prince of the Moon Kingdom and Milky's older brother. He appears as Eclipse at the beginning of the series. His whip attacks are identified as Eclipse's. Whenever Shade goes out, he usually dresses up as Eclipse. He was obsessed with the power of Prominence because it had the ability to save Fushigiboshi. He knew about the blessing of weakening the sun. He has a mysterious yet serious aura about him in the first season, but he turns out to be very kind. Shade is very intelligent. He helped the twin princesses in the first season. His mother, Moon Malia, is very sick, and he cares for her wholeheartedly. It is for her that he aspires to become a doctor. He has a pet dragon named Regina. He has a conflicted relationship with Bright. At first, he seems to be disliked by anything due to her cold attitude, but he develops a crush on Rein. In the second season, his interest turns into unrequited love for Rein. His role became less prominent in the second season, but he continued to protect Rein. In the anime, Shade remains in love with Rein and demonstrates his love with "flowers of happiness."

Milky is the princess of the Moon Kingdom and Shade's younger sister. She's a toddler that can travel around places (by sitting on her floating star). Milky is more likely to have trouble communicating people with her "Babu" babbling, but people like Shade and Fine can understand what she means. She is also gluttonous like Fine, and often eats up all of the food before Fine can reach it. She likes Narlo.

Regina is Shade's pet dragon that he used to travel to all the countries.

Moon Malia is the queen of the Moon Kingdom and Shade and Milky's mother. Her mood and health is measured by the aurora waves floating in the sky. She is usually sick. She is very fond of Rein in the manga.

Chuuba is a very accurate rat fortune teller.

Monmon Golem is the beast that sleeps deep inside the temple. At certain times of the year, he wakes up and blows the obscuring clouds away from the moon to allow moonlight into the Moon Kingdom. Momon Golem also haves different tastes than ordinary humans because he can eat Fine and Rein's cooking and even called it delicious.

Queen Scorpion is a very big scorpion that comes only when her little scorpions get defeated. She is very sensitive to loud noises.

Mia is a local worker near the Star Lake.

Flame Kingdom (Lee-on-eh)

Age: 11 (1st series), 12 (2nd series) Lione is the princess of the Flame Kingdom and Tio's older sister. She has orange-reddish hair and hazel-brown eyes. Lione is too personal and often takes thoughts deeply. Also, Lione is not very fond of dancing, but she knows how to samba. She even knows how to cheer Tio up. Lione has some useful skills like driving and being able to tell how Bo Dragon is feeling. In the manga it is shown that she is most closest with Rein than all the other princesses of Fushigi Boshi

Note: It is shown that Lione did Samba dancing for the first time at the annual Samba party the 32nd episode. Note: It is shown that Lione was using a special stone/gem to see how Bo Dragon was feeling in the 3rd episode.

Lione is a gentle princess who's caring and sweet. She is shy and sometimes nervous, but she is never afraid to try. Also, she is very loyal to her kingdom and would do anything to save it. She has reddish-orange hair and hazel-brown eyes. Lione loves Flame Kingdom as much as she loves her friends, Princesses Rein and Fine of Sunny Kingdom. She is half lion and half human.

Age: 9 (1st series), 10 (2nd series)

Tio is the prince of the Flame Kingdom and Lione's brother. He likes to play with his katana (saber). Tio often makes appearances because he tries to save Fine and Rein from trouble. He always fails every time he saves the twin princesses. He sees Shade as his hero and asked Shade to be his assistant.

Wohl is the king of the Flame Kingdom and Lione and Tio's father. He is very dynamic and his excitement is emphasized by the torches in the throne room.

Nina is the queen of the Flame Kingdom and Lione and Tio's mother.

Howan is a cook and a manager of a Chinese-style restaurant in the Flame Kingdom. The special‐feature menu of his restaurant is Flaming Hot Fried Rice (Heramera Chaofan).

Bo Dragon is an extremely large dragon living inside the volcano. When Bo Dragon is sick, he coughs volcanic ashes.

Thunderbolt is a creature with two flame tails. When Shade rides on Regina, Tio rides on him. He is sometimes incompetent with Tio. Thunderbolt's best appetite is Poomo.

Water Drop Kingdom

Age 10 (first series), 11 (second series) Mirlo is the princess of the Water Drop Kingdom. She is a shy and soft-spoken girl who does not wish to offend others, so she tends to go with what others say, especially her mother. In the original concept and series, Mirlo is a talented artist and often shown painting landscapes of the castle and the city and countryside surrounding it. She also takes care of her younger brother, Narlo, often.

She won the Best Sports Princess Party in spite of her lack of athleticism thanks to her sportsmanship and helping get the contest back on track after the fight between Altezza and Sophie. She was going to marry Estevan, the young son of wealthy businessman, in order to get the funds to fix the Drop Kingdom's cloud making machinery, but Fine and Rein exposed it as a plot by Roman to install a puppet on the throne. Mirlo admits she is not ready to marry, but the businessman will help pay for the repairs anyway. Although she usually acquiesces to her mother, she found the courage to tell her to spend more time with Narlo.

In the second series, she received an anonymous love letter that turned out to be from Pastel, the prince of the Art Planet, before he had to leave to tend to his ailing father.

Mirlo is a much different character in the manga. A vain and spoiled girl, she causes trouble for Fine and Rein. While it appeared she was meant to a primary adversary for the twins, she disappeared after the third chapter until a brief appearance in the final chapter.

There was some confusion as to how Mirlo's name is to be spelled in English. In the show, it was spelled Mirlo in one instance and Milro in another. Similarly, the first Character Detail Book spelled it Mirlo and the second Milro.

Age: 1 Narlo is the prince of the Water Drop Kingdom and Mirlo's baby brother. He is about the same age as Milky.

After the events at the Flame Kingdom's New Years Talent Show, he began to call for his mom by yelling "Gabin!!" ("Gabin" means "Oh my GOSH!" in Japanese.) Both Bright and the Twins tried to break him of the habit, but got him halfway to "Ma-bin".

Nalro seems to have a crush on Milky and starts riding with her on her star.

Unlike Mirlo/Milro, Narlo's name has been spelled consistently in English in show-related material.