How can anyone give oral sex to someone they meet casually on the forum, surely this is most distastefull, apart from being too risky from disease and infection.
I would have to get to know someone very well before I could bring myselt to perform such an act, according to the posts I have read, people are quite willing to do this on the strength of an advert, a stranger whom they have never met and know nothing about.
Also, the same principle applies to sexual intercourse and full penetration, to exchange body fluids with a total and complete stranger is foolish in the extreme, dangerous and lacking in any thought of basic hygiene.