Ryuu is a female Elf with sky blue eyes and green hair. Her hair was originally golden blonde until her hair was dyed green by the other employees of the Hostess of Fertility. She is mentioned to be extremely beautiful with skin as white as snow, causing her to be referred to as a fairy on several occasions, and even making Bell wonder if he had wandered into a fairy tale.
Ryuu is often seen in a green maid outfit with a white frilled headband, matching white apron, and a pair of brown boots over black leggings.
Her adventuring attire includes a green flower-shaped hood and a white sleeveless top underneath. She also wears a pair of long, brown gloves and boots with a white sash around her waist where she keeps her wooden sword and a pair of short swords
Ryuu is calm and stoic but also cares deeply for her friends. She is strong due to her past experience as an adventurer. When a person related to her or her friends are in danger or in need of help, she is always ready to step in and help no matter the cost.
Like many Elves, Ryuu is selective with who may touch her. However, she has been advised by Alise to not let go of a man that was able to grab her hands, and began to follow Bell with her eyes. Unlike some Elves though, she doesn't bear the same hatred towards the Crozzo family or their magic swords for their role in the destruction of the forests the Elves lived in, stating that the event took place many years ago and that her village wasn't directly affected.
Ryuu was the member of a family that cared for the sacred tree in their home forest of Ryumilua. As time passed, she began to think that beautiful Elves were the ugliest of all people, due to seeing her fellow Elves' behavior toward those of other races. No matter how much she tried to forget it, once she began thinking about it, the thought firmly planted itself in her mind. Eventually, the thought became enough to make her decide to leave the forest.
After arriving in Orario, Ryuu became an adventurer known as Gale, belonging to the Astraea Familia. She was caught in a trap set by Evilus and all of her fellow Familia members were murdered. Overcome with vengeance, she persuaded Astraea to leave Orario as she didn't want her to see her revenge. After that, she single-handedly destroyed the Rudra Familia as a part of her rampage and those associated with Evilus through various trickery, traps, and assassinations, causing her to be branded as a fugitive as a result of the ensuing chaos. Her revenge finally fulfilled, she collapsed in an alley where she nearly succumbed to her injuries. Fortunately, she was discovered by Syr and nursed back to health by Mia Mama. Ever since then, she has joined the Hostess of Fertility.
Concurrent Chanting (並行詠唱): A high-level technique involving casting magic while fighting or moving around. Its difficulty is likened to dealing with a bomb with both hands while fighting due to the chance of failing a chant or not being able to control their own magic power. Lefiya Viridis observed that Ryuu was far more skilled at it than Riveria Ljos Alf.
Luminous Wind (ルミノス・ウィンド): Luminous Wind is Ryuu's wind and light element wide-area offensive magic that summons green stardust to attack her enemy.
Noah Heal (ノア・ヒール): Noah Heal is Ryuu's healing magic. It is capable of healing wounds and restoring the target's stamina, though unlike the effects of potions it takes time to heal. The effect of magic depends on the surrounding environment. Effect rises in forested areas.
Fairy Serenade (
Mind Load (
Aero Mana (
Hunter (狩人): Hunter improves abilities against monsters Ryuu has fought before and gained excelia from.
Abnormal Resistance (耐異常): Abnormal Resistance negates the effect of abnormalities such as poison.
Magic Resistance (魔防)
Kodachi Futaba (小太刀・双葉): Kodachi Futaba is a pair of short swords that Ryuu received from Gojouno Kaguya. They are sharp and are considered to be fine works among all second class weapons. These were the only weapons that she didn't leave on the Astraea Familia grave.
Alf's Lumina (アルヴス・ルミナ): Alf's Lumina was an order made wooden sword created by the Goibniu Familia from a branch of the holy tree in Ryuu's home forest of Ryumilua. On top of having high attack power and durability, it had the ability to amplify magic. It was highly compatible with Elven magic power and could be used as a staff. It was destroyed during her fight against the Juggernaut in volume 13.
- Originally, Ryuu referred to Bell by his surname, calling him Cranel-san. Despite this, she had referred to him twice by name; once during the battle against the Black Goliath, and the second time after he was hit by the Juggernaut's tail. After their return from the 37th Floor, she refers to him by his name.
- Ryuu once had a bounty of 80,000,000 valis placed on her.
- The author mentioned that Ryuu leveled up every level until Level 4 at a one year to one and a half year pace.