If the other person is a minor, it is a very serious situation. It might be considered a "leud act," which is a violent felony and one for which you would have to register as a sex offender for life. This is true even if the minor is a voluntary participant. IIf you were to photograph or video tape the incident with the minor, more problems could result. Place such images on the internet and you could be in even more trouble.
If the other person is a consenting adult I see no particular problem. Of course, there are always aberations, but generally, consenting adults in the privacy of their own homes have a privacy right. Paying to have sexual relations is a crime ("prostitution," which includes any leud act between persons for money), and you should always be aware of undercover cops. Be very cautious! While the direct punishment for the offense might not be that significant, you could end up being convicted of a strike offense, and many if not most sex offenses require registration as a sex offender, that is a very serious consequence.
You would be much safer to find someone who shares your preferences with whom you can experience mutual satisfaction without having to pay for it.
Atotrney Broughton has given you a fine analysis of the law, but the fact is that virtually every prosecutorial office and police department in California will make an arrest and pursue prosecution for prostitution on the facts you offered in your question. And if you have used any form of advertising, Web-sites, or social media for making the arrangements, there is a strong likelihood that you are on the radar of law enforcement.
It only gets more complicated and more serious from there with considerations of minors responding.
You are treading in dangerous waters and you should consider whether that is part of the appeal of the situation to you. Take a look through the Avvo archive at the vast number of Californians who are desperate to undo a sexual-offender registration obligation. There are better ways to pursue your interests that do not involve payment for services.
My responses to questions on Avvo are never intended as legal advice and must not be relied upon as legal advice. I give legal advice only in the course of an attorney-client relationship. Exchange of information through Avvo's Questions forum does not establish an attorney-client relationship with me. That relationship is established only by individual consultation and execution of a written agreement for legal services.