Man, the idea of a Super Saiyan Demon is like mixing fire with nitro—absolutely explosive! From what I've gathered from 'Dragon Ball' lore and fan theories, this hybrid would likely have the raw, untamed power of a Saiyan's transformations cranked up by demonic energy. Imagine the golden aura of a Super Saiyan, but tinged with dark, crackling shadows. Their strength would probably surpass regular Super Saiyans, with a side of chaos-fueled abilities like reality warping or life-draining, depending on the demonic source.
What fascinates me is how their personality might shift—demonic influence could make them more aggressive or even sadistic, contrasting the Saiyan's battle-loving but often noble spirit. Think Vegeta's pride fused with Janemba's unpredictability. And let's not forget stamina: demons rarely tire, so they might maintain transformations longer or even evolve mid-fight in terrifying ways. The potential for storytelling here is insane—I'd kill to see Toriyama sketch this!