YES! I have had the same fantasy/curiosity as well! I have a long term girlfriend who I love but I have been thinking about receiving giving oral with a guy. When I'm out and around, I never check out guys and am always looking at girls and never think twice about any guys, nor do I look at them.
Typically, I think about this more when I'm at home, just thinking about the sex part. With that said, I think I'm a lot like you since I don't feel "attracted" to other guys, just turned on by the idea of sex. It is hard to make sense of wanting to do oral but not wanting to kiss or cuddle, as well as not having any emotional attraction (or really physical, beyond cock, for that matter).
It is all a bunch of strange, hard to define ideas like this that don't really make sense to me. Yeah a lot of people on here are just saying "go for it" or whatever, but at least for me, it is more complex of a feeling than just wanting to suck/get sucked. You know what I'm talking about Lebron?