Legallity of contract that obliges a signatory to perform oral sex?

Question

In the American animated series South Park, in Season 11 episode 10, a character is contractually obligated to perform oral sex.

I imagine this contract would be illegal to enforce? My suspicion is that if the signatory changes their mind, then current consent trumps prior consent. Otherwise this would be court enforced rape?

Two questions follow:

1. Could oral sex be legally enforced by a contract?
2. Could including this clause invalidate an otherwise legal contract? E.g. contract says pay 5 dollars and perform oral sex. Could the first part can be enforced, by ignoring the latter? Or does the inclusion of something illegal invalidate the entire contract?

I realise this is probably a stupid question, but it appears to be on topic - meta.

Answer 1

CRS 18-3-402 states that

(1) Any actor who knowingly inflicts sexual intrusion or sexual penetration on a victim commits sexual assault if:

(a) The actor causes submission of the victim by means of sufficient consequence reasonably calculated to cause submission against the victim's will

which is to say, sex must be consensual. The essence of a legal order for specific performance is that the party's "consent" is irrelevant. This is not limited to Colorado, and would hold in any jurisdiction where prostitution is legal. A court would not order specific performance in this case, neither in Colorado nor Nevada. Nor would the court order specific performance in case the contract allowed one party to beat the other to a pulp.

The contract itself is illegal in Colorado, but not in Nevada (certain counties excluded). In that case, the other party is out $5 in Colorado. In Nevada, they would be entitled to a refund (amount to be determined, depending on the facts of the meat pie).

Answer 2

I know the OP asks about Colorado, but the perspective from England and Wales may be useful too.

Contracts for prostitution (and oral sex would almost certainly fall under this) cannot be enforced. Prostitutes cannot sue for payment because the contract is considered contrary to public policy; customers cannot sue for performance because sex is not viewed as good consideration, so the contract is void.

I don't know why a different reason is used in each direction (either reason seems good enough to me), and different jurisdictions may have different legal theories covering this - but the bottom line is "oral sex cannot be enforced by a contract" (question 1).

The answer to question 2 as you posed it, is that there is no consideration, so there is no contract. If the contract said "Morgoth will pay 5$, and Martin will give them a meat pie and a blow job", then there would be consideration in both directions and a good contract. You could sue me for your meat pie ... but not the blow job.