It is not like oral sex is new. It is not like we talk about it. It is not like there are tons of manuals, how to articles and advice on the subject itself......
Wait...never mind the last part.
None: people who refuse to have, discuss or even hint about any mouth-genital contact.
Reciprocating duty: Will perform oral sex in the deal maker of receiving oral sex. The rush job to get to the real pleasure of the evening. The 'I do you-you do me' rule of play.
Oral occupation: Oral sex is a job, a job that is well planned, well done and deserves rewards and awards. The get down to it, stay to enjoy it and then plan on returning really soon.