A lithosexual might feel sexual attraction to someone, but doesn't want that feeling reciprocated, and if it is reciprocated they have a good chance of losing that sexual attraction to that person. It might be out of discomfort at the thought of being perceived as '"sexy", or it could simply be an unknowable factor, but whatever the case, a lithosexual is most likely not going to seek out a sexual relationship.
Meanwhile, a reciprosexual doesn't feel any sexual attraction to anyone unless they know that the person is attracted to them first. So, no one is sexy baseline, and then someone lets them know they're sexy, and they might feel sexual attraction to them in return. As such, a reciprosexual doesn't initially seek any kind of sexual relationship either, but for wholly different reasons.
Note that the former is not specifically the same as being attracted to someone who rejects you (though it might cross over to that), and the latter isn't waiting for someone to say they think you're hot in order to confirm your feelings. In the case of the lithosexual the person they find sexy could simply feel neutral towards them, and a lithosexual isn't exactly going to present their feelings out loud, especially not after experiencing a few times where they do and are told the other person is attracted to them and the attraction disappears. Better to simply keep it quiet, because it's a no-win scenario. If they don't find the litho sexually attractive, then they're stuck with your feelings for them, i.e. the same as before. If they do find the litho sexually attractive, now the litho feels nothing for them and they might get angry, like the litho led them on. Meanwhile, a reciprosexual doesn't feel any sexual attraction at first, and so the only point at where they do feel it is if someone tells them they're sexy, thus they're not waiting on anyone to tell them this, there's no anticipation. Possibly surprise, but no anticipation.
