okay, i'm back, and with the image this time. first off, fire is semi-transparent. so none of them look like flames. admittedly, my own don't look exactly like fire either, but they give enough visual that you can get the idea. it somewhat helps that there's bright glow around the wings, and a light on the trees signifying that the wings are glowing, and the color makes it look like fire. for butterfly wing-like fire wings, you'd want to make it similar to a swallowtail's bottom wing shapes. they have a sharp ridge in the middle and smaller ridges along the rest. for liquids, tone the transparency based on what it is. if the liquid were a non-newtonian fluid like ooblec then it wouldn't really be transparent, for slime it would have some transparency based on which slime you're basing it off of. if you're going for a fluid, make the wings either a little warped or a little droopy. if going for fire, make little wisps going out. outline is clear, but still a tad bit transparent, and the inside is just differing values of transparency with the appropriate colors and make wisps out of the lines at the end to signify the ends of the fire. if it's a contained fire, there should be wisps of nothing going into the wing, mainly also from the ends, but also a little from the top.

oh and my personal fav is e. b looks the most like lava, but e looks like real hot flames. on the open-top stoves, blue flames are seen cuz blue is hotter than the normal orange.

flames flickering over the wings rather than the wings being made OF the flame

one more to add! this one is the final contestant I think.

edit: the blue around the tuft of fur on the face would end up being highlights for its fur I think and under the outline

aaaaaaaand neever mind! I've decided to go in a completely different direction! the final result for the wings will be... this dude!