Someone that is both dominant and submissive is a seke. http://www.mangaupdates.com <---- go there and put in seke. Seme, Uke, and Seke can actually apply to straight relationships too but in manga they are used nearly exclusively as yaoi terms.
The great thing for gay men,they could do it both ways. Just that they need to compromise.
Some guys read it, but it's not their target audience. Bara on the other hand is made for gay guys. Does this mean gay guys don't like yaoi? No, the same way like some guys like chick flicks, however if you understand the audience that this is written for, you'll get why switching is pretty rare. This isn't a blanket statement about peoples personal taste, but if you don't understand that you really don't understand yaoi. Yes there are some rare yaoi that aren't like that as much, but they are rare. Junjou is really written with women in mind. I like it, not saying that I don't, but I'm also self aware that it's targeting me as an audience. It's again not a bad thing, but you need to be aware of it.
Wine is correct. The majority of yaoi is created by women for an audience of women (though of course as with anything, there are exceptions.) The point of yaoi is to remove gender barriers to allow women to explore thoughts of sex and sexuality without carrying all of the societal baggage that is dumped on women. It really has nothing whatever to do with gay sex. In real life, gay sex doesn't focus nearly as much on anal sex as you see in yaoi. The emphasis on penetration in yaoi is for women readers, who do not relate to blow jobs or frotting.
Right back atcha. I did say there were exceptions but it is silly to ignore the clear point and purpose of yaoi.
What part of what I said didn't say that it's ok for to have your own personal taste? Everyone has them, which is why it's called personal taste. Even the yaoi you mentioned was written by a female for a female audience. (Just like some guys like chick flicks and some girls like guy flicks, it still doesn't change the demographics that they are going after when they make that kind of media.) You claim other people are only saying stuff to feel good about being right, when you are talking in circles. All I did was point out a fact to the original question being asked.
I think in the yaoi universe, it has a lot to do with plot. All the manga where the main characters dispute who gets to be seme or uke, there would be no story if they were all seke. Then there's the manly seme and pretty ukes - not everyone wants to see what looks like a little boy doing a hunky guy, tho I have nothing against it. IMO, seke characters would actually make for more plot opportunities.
Why is it always top or bottom not both, my gay friend told me lots of guys do it both ways