The plural form of clitoris is clitorides. It's pronounced clit-or-i-deez.
Don't believe me? Then believe this.
That such a form exists is not shocking. In fact, I would consider the English language remiss if there were no plural form of this particular noun. After all, why should it be treated any differently than all the rest of the nouns? Call me a linguistic equal opportunity employer.
The unavoidable fact is, however, this word is probably only used in the most clinical of applications, ("the clitorides of the control group C3 subjects did not respond to the stimuli with same vigor as those of the subjects in test group B1").
Despite this sophisticated option, unfortunately, the infinitely more likely representation for a plural manifestation of the quintessential female sex organ will be that familiar slang word that starts with C and ends with T and has an S tacked on after that to indicate there's more than one. The word also includes one other consonant and one vowel (not U and not N--think hard, the slang word is a simple truncation of clitoris--got it?). Furthermore, the reader or hearer of the slang version will know exactly what the speaker or author means.
Not that I know for sure, but the author's or speaker's assertions of all those clitorides, methinks, are likely a bit on the dodgy side. (Come on now, buddy, tell the truth. Was there really more than one?)
I will concede that if said author is Hugh Hefner, there might be some veracity to his claims of swarms of clitorides. I would furthermore offer the pop icon of bunny eared fame the following in the interest of checks and balances: at your age, Hef baby, wearing pajamas all day long is not necessarily viewed as an elective decision.