Art done by  oddbird whom I greatly admire, and am incredibly grateful to for doing this.

I've sat on this a bit longer than intended, but this is my new design for Sunaseth moving forward. This is the SFW version of it, without the accessories pictured in the NSFW variant because I would like to show him without the accessories as well. A proper ref has been a long time coming I must say, and I'm glad to have it done for sure. This was a birthday gift from my husband  dragondraikk and I'm thrilled with how it turned out. I've only waited this long to post it since I've had trouble finding the things I want to say and how to word the descriptions of Sunaseth below.

Regardless, it is here now. Or at least most of it, the exact details shift and waver in my mind depending on mood which is part of why this has been so hard to pin down and why I haven't uploaded this lovely work that's been done for a good while now.

Either way, the TL;DR is that he's a dragon from a tribal setting that was captured at a young age by a more technologically advanced people who had just found their way to his home. His species like to paint themselves for communication purposes and for social signalling and such, as shown by him painting himself with such a happy little look. Sunaseth spent most of his life in a laboratory but was able to escape, and his story generally starts after he's escaped.

Anyway, below is a bit of a typed up thingy.
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Sunaseth as I've imagined him lately is a dragon that hails from a previously unexplored continent, a land that has been seeing short bursts of exploration from a much more technologically advanced society of anthro sorts. His home continent had been unexplored for a very long time due to difficult ocean currents surrounding the location making it impossible to get close, but the anthro explorers were finally able to make landfall there with the advent of steam powered ships. Sunaseth was one of the 'specimens' captured for study and spent most of his youth held captive in a lab, something which has had an effect on him in a few ways.

First, his capability to breathe fire has been removed. Originally his firebreath was powered by a pair of chemicals that combined to create flame: one chemical that was produced in large amounts that served as the primary fuel, and a secondary component that when mixed with the fuel and exposed to air would undergo a combustive reaction and ignite the fuel chemical. The lab folks weren't too keen on getting broiled alive, oddly enough, and after discovering how the firebreath worked properly from an autopsy of a deceased member of Sunaseth's species opted to surgically remove the 'starter' organ from him, leaving only the fuel producing organ. The fuel alone cannot combust: it requires a secondary source of heat to ignite, and Sunaseth's species capabilities as a living fuel source were seen as a worthwhile risk.

Second, Sunaseth's mind and body were subjected to various experiments and attempted training methods. This has left him with a relatively easygoing disposition, and a tendency to do what he's told without thinking through it at first that he must actively fight against, if one can find the right way to phrase the request and the right tone to deliver it in. As well, the separation from his kind for so long has left him with a desire to seek affection and praise and a fear of loneliness. He has a superb constitution from dealing with a variety of drug treatments and the like during his captivity, though some substances may effect him in unusual or unintended ways.

Third, he has learned to be quite patient and how to lull others into a false sense of security around him. After all: he's not in that lab anymore, and they didn't let him go. All it took was for him to have a single day out of the couple decades he was held captive where his captors were a bit too lax about keeping sources of open flame away from him. One forgotten lighter that they were sure he wouldn't even know how to use, and he was able to burn away the chain holding him in place and start incinerating the rest of the lab. Or at least enough to escape. Though he has nowhere to really go, he roams the strange land he's been brought to and seeks meaning in his life. As to what he might find after his lengthy stay underground, who can say?

He remembers the songs his people sang. He remembers the way they would paint one another's scales, and remembers the markings his parents showed him. He still enjoys the touch of paint on his side, and even if he's forgotten what all those markings mean he still feels a little happier with them on. He knows how to mix up his own paints from scavenged ingredients, and how to store them in little pots to keep them there. How to tie leaves to a branch to mark his scales with color, enough to make any of his kind burn with envy. He remembers many things. And he learns many more each day. While he spent most of his life being thought of as nothing more than a simple, brutish beast, he's keenly intelligent and able to manipulate his environment to great effect.