Unlike many of the Dragons presented, she is shown as a quadraped instead of a biped. Her eyes and claws are dark blue, with much of her body a light lavender color. the other spikes on her back, legs, head and tip of the tail are grey.
Scarlett is fairly friendly towards others around her, though this was mostly towards her own kind, her believing that other dragons wouldn't hurt eachother. She became more sky and uncomfortable around other species, mainly for the reason that they weren't dragons like her and Spike.
Not much is known about Scarlett's life, though she tried to make friends with other ponies. However, she had been bullied by some Ponies, who at one point got her under a rock and called her a rock dweller and a freak lizard. This made her very uncomfortable around other species as Dragons didn't treat her that way.
She left her home and stopped over in Equestria for a week long spring trip, setting up a picnic of Gemstones she made herself when she first met Spike. She was a little shy at first but eventually warmed up to him. She and Spike continued meeting for the next few days until Spike decided to show her to his other friends. She began to show concern as they were heading to Ponyville. She stayed with Spike when first seeing the other ponies and Gems, and eventually left them altogether. Spike found her back at the picnic site, and explained to her that not all ponies were as bad as the ones she met, just for the Salamander Monster to attack them. When the others arrived, she told them what happened and had to gather herself to follow them in order to save Spike. In the end she began to open up a little bit to the other species, and upon leaving, hoped to find other nice creatures like them.