Not for speed though. Any of those swinging machines from the theme park would swing a succubus faster than the succubus herself would normally fly.

Their small succubus wings are a major factor to their slow flying speed, despite their exceptionally light body weight (ie. they are as light as a body pillow when they straddle you). They can still fly fast but it can’t be sustained for more than 30 seconds because, again, to keep their weight low, a common succubus wouldn’t keep a large reservoir of energy in their body. Those that do choose to keep a large reservoir through their jiggly badongus would conversely have an increased weight thus lowered flight capabilities.

Either way, a freshly fed succubus could easily fly fast by using its still warm human fuel that was deposited in her lower body reservoir. But then, they often don’t have the need to fly fast anyway because their fuel station isn’t an upright hero who would smite them for pumpjacking his oishi no oil well. However you gotta think a lot about the feeding habits of your monstergirls. Succubi don’t have as efficient of a fuel source, so would obviously be worse in a flying competition than, say, a harpy.

Harpies subsist primarily on meat, though they can eat fruits and grain as well. It’s hard for them to cultivate it themselves due to lack of hands, so they have diets largely based on a hunter/gatherer model, and this calls for much superior flight skills, not only for chasing prey, but also killing it, as they need to remain airborne to effectively use their talons. The weather is also a factor, as a lot of harpies tend towards more mountainous regions where the wind is a lot more wild and unpredictable, meaning they need to be much more naturally talented and strong to deal with.

Succubi only need to develop their flight skills to traverse Hell, which has little to no variance in weather, having consistently warm updrafts to get airborne, and minimizing the need to flap to raise higher.