Hi all--as the originator of the conditions list, let me add a few comments. . .
On the topic of males being able to become Aroused as a free action and females not; this was meant to reflect how a guy can get hard at the drop of the hat, free hand or external stimuli not always required.
Now, I could be way off here, but physiologically, a woman getting physically aroused in the same manner does not seem likely. Not without her or someone else acting upon her in effort to bring about that result.
Next, as far as Horny being like "animal is in heat" or an "overwhelming need for sex," this was not my original intent. . .'Aroused' is the physical condition, and 'horny' is the emotional condition. I separated these as disparate elements because it IS possible to be one and not the other. Neither one of these is meant to be an extreme condition.
So YES, horniness IS something felt by humans. If you want a condition to cover a being in heat, then make one called "Estrus" or simply "Rut" and go from there.
An example of a character who is Horny but not Aroused would be guy suffering from Impotence. He wants sex, he is thinking about sex, he feels lust for any sexually compatible partner he meets, but he cannot become Aroused, and therefore is one frustrated guy until the Horniness subsides.
Anyway, Lilly challenged me to speak up on this, and I have. The new stuff looks awesome and i am looking forward to the first book coming out. At the moment, I am still working on material for the Hentai edition, although I am waiting for the Book of Vile Darkness to come out so I can see if there is any overlap.