Sexual Attraction: Feeling sexual desire or having sexual thoughts for someone or something. Libido: Having a physical desire for sexual release. Sexual Arousal: The physical response of a body when it is preparing for sex or is sexually stimulated.
These three things often overlap, but can occur separately. Sexual attraction often causes a libido spike, and a libido spike often causes sexual arousal, but "often" =/= "always"/"for every person."
An asexual can have a libido. A non-libidoist can be allosexual. A person can become sexually aroused even if they are unattracted to someone, or are not experiencing a libido spike.
You can have sexual desires/thoughts for someone (sexual attraction) but no physical desire for sex (libido) - or vice versa. You can become sexually aroused from random stimulation (ie; rubbing genitals against something on accident) or from random hormone spikes.
This separation is necessary when explaining the asexual spectrum and allosexual spectrum to people.
