Vaginas exude a large amount of heat on normal human women, let alone on certain female half-scorpions, whose body temperatures would only naturally be much higher than a normal human's. If one were to approach Scorpia's bare vagina, especially if she was aroused, you would probably be able to feel the heat of it on your skin. The natural heat is also probably conducive to arousal in its own right.
Much like a 15 year old going through puberty and getting erections at random, a side effect of being a half-breed is probably often, unprovoked arousal. Who knows, it may even be permanent. Shyvana might literally be "in heat" at all times. On top of what may be almost perpetual wetness between her thighs, her naturally high body temperature probably makes it difficult for her to wear human clothes comfortably (especially tight, reinforced armor).
She probably sweats profusely in her armor, enough to drench herself in only one short outing to Bright Moon. But then again she may get off on the feeling of being wrapped so tightly, so to speak. The sensation of her wet vagina would probably resemble putting your finger into a bath of hot honey. The juices more viscous than normal and just hot enough that you almost risk a burn.
Imagine the smell and the taste of her inner thighs after one battle. Wet and sticky with a musky odor and all salty-sweet from the combination of her various juices.