Sapphire is a young woman with mid-length blonde hair and bangs that frame her face with a single strand falling in the middle. She has downturned blue eyes, heavy-lidded with visible eyelashes on both her upper and lower eyelids, giving her a wistful, doe-eyed look. Her lips are full and plump, and her eyebrows slope downwards, accentuating her expression.
Her outfit consists of a short green dress, sleeveless with a ragged hem and a plunging neckline. She wears the village rope around her neck, wrapped twice and tied in the front with a bow.
Sapphire seems to spend a lot of her time thinking about boys. Out of the three sisters, Sapphire wants a boyfriend or husband who's primarily handsome rather than strong or a provider.
She is first seen along with her two sisters discussing the outsider, Senku. She argues with Garnet that the more important thing about a man is looking cute rather than being strong. They're later shown vaguely discussing love, lounging on a set of rocks in their bikinis while Suika listens in on them.
In the fight between Argo and Ginro, Sapphire shrieks with horror at how beaten up Ginro looked following one of Argo's barrages of hits. She then appears disgusted alongside her sisters when Ginro tells everyone his plans to have everyone have a harem.
In the anime, after Kinro is given glasses, Sapphire comments that she likes them.
When Senku makes cotton candy, Sapphire is shown in ecstasy over how delicious it is. After Senku asks Gen about Homura, Sapphire and the others assume he's interested in a girl. However, Senku reveals Homura is spying on them.
On Christmas, Sapphire is amazed at the beauty of the large tree Senku lit up with light bulbs. Later, when everyone is looking for special rocks for Senku to use as a better filament, Sapphire holds something up, Ruby holding something similar and comments it looks like a gemstone. As it turns out it was just a beetle husk, which makes Sapphire drop it in disgust.
- She is named after the gemstone, sapphire. The most common form of the gemstone is the blue shade, which Sapphire's eye colour mimics.
|Male||Alabaster • Argo • Carbo • Chrome • Ganen • Genbu • Ginro • Hagane • Jasper • Kaseki • Kinro • Kokuyo • Magma • Mantle • Natri • Sagan • Sho • Soyuz • Tetsuken • Titan • Unmo|
|Female||Alumi • Azura • Beryl • Dia • En • Garnet • Kohaku • Kujaku • Namari • Ruby • Ruri • Sango • Sapphire • Shirogane • Shovel • Suika • Suzu • Turquoise|
|Unknown||Chalk • Sagara|
|Alabaster • Argo • Carbo • Chrome • Ganen • Genbu • Ginro • Hagane • Jasper • Kaseki • Kinro • Kokuyo • Magma • Mantle • Natri • Sagan • Sho • Tetsuken • Titan • Unmo|
|Alumi • Azura • Beryl • Dia • En • Garnet • Kohaku • Kujaku • Namari • Ruby • Ruri • Sango • Sapphire • Shirogane • Shovel • Suika • Suzu • Turquoise|
|Soyuz's father • Ibara • Matsukaze • Mozu • Oarashi • Soyuz|
|Amaryllis • Kirisame|