Cheerful autistic nerds, Helioses are driven to the point of recklessness, extremely self-sacrificing, and have a strong sense of justice. They're prodigies at maths and engineering, often able to tinker with and create useful trinkets and machines from a young age. They're people-pleasers and have very low self-esteem and a lot of impostor syndrome, and often feel the need to constantly prove themselves and "be useful".

They often have some kind of congenital physical disability which compounds their feelings of inferiority (regardless of whether their environment is supportive or not). However, it typically gets "fixed" by the plot, and frequently by their own ingenuity. In settings with overt magic they become exceptional magic users, and in settings with magic based on devices or magical constructs they will almost always be drawn to it. They're straight but interested in bihacking in worlds with homophobia and bi in worlds without, and they're obligate poly.

They're based on Hero, a minor side character from Worm and as such that instance is their most central one, but their instance as the Warrior of Light from Final Fantasy XIV is also pretty central and his most developed one.

Good threads/continuities to be introduced to the character are Aetheryte and Yggdrasil.