Stevonnie is one of the shortest fusion Gems in the series. They are taller than Amethyst and Pearl but a few inches shorter than Garnet. They have an average/athletic build consisting of Connie's slim figure with Steven's chubby features. They have dark, curly hair that reaches past their hips, and a fair skin complexion similar to Steven but slightly darker. They walk around barefoot and their attire consists of Steven's star shirt as an undershirt with his jeans turned into shorts while also having Connie's turquoise dress as a crop top. They take on the appearance of a teenager, around the same age as most of the teenage characters, such as Lars and Sadie, if not older. They are considered to be very beautiful, as the characters in Beach City seem to be in awe of their beauty.
Stevonnie's personality is unique. Because this is the first fusion between a half-Gem and a non-Gem, they do not have the combined mind that is common with Fusion Gems, but instead, share the personality of both Steven and Connie. Stevonnie carries the free spirit, love, and fun-loving attitude from Steven, but also carries the courtesy, awkwardness, and intelligence of Connie.
- Amethyst is the one who came up with the name "Stevonnie".
- Stevonnie is the first Gem-Human fusion shown.
- While Steven is the primary instigator of the fusion, it appears that Connie is the dominating personality.
- They are the fourth Gem to not feature their weapon.
- Stevonnie's portrayed age may have been created by combining Connie's and Steven's respective ages together.
- Despite their older appearance, however, it is likely that Stevonnie is still the same age as Steven and Connie.