Raphael from Baldur's Gate 3, weights 0.7-0.9 for best results
Trained on Pony Realism since all the images are screenshots from the game and focusing on realism made the quality better. Overall quality ranges from good to mediocre... I'm gonna try to train a more cartoony version next
Recommended tags: "demon boy, multiple horns, demon horns, colored skin, red skin, colored sclera, black sclera, demon wings, demon tail" for his Devil form and just "brown eyes" seems to work for the human form. His normal outfit is tagged as "frills, ruff (clothing), formal" and the Haarlep outfit is "harness, chest harness"
Put "Sketch, cartoon, anime, cgi, illustration" etc. in negative prompt