I personally know one girl whom, when she was 8, actively went into sex chat rooms and flirted with older men (anywhere from 16 to 40). I don't think she actually had physical sexual experiences with anyone, though.

I personally know two girls who have had sexual intercourse with adults, one when she was aged 5, the other 8. It was rape in the sense that they were explicitly nonconsentual (they explicitly said didn't want to do it), but it didn't traumatized them. One theory might be that "doing stuff you don't want to do, but adults tell you to do, so you do them anyway" is pretty common at that age (e.g. being forced to clean your room).

I suspect the sex act itself isn't "pleasurable" for them, but having "sexual relationships" with adults may be pleasurable (since the first-mentioned 8 year old sought it out). It may be seen by many of them as a neutral act (like the 5 and second-mentioned 8 year old) and a form of curious exploration.

This is assuming, for lack of a better term, "gentle loving pedophilia". The way pedophilia is often portrayed by mainstream media is violent rape, with screaming, kicking and blood. While I don't personally know of any girl who actually experienced "violent rape pedophilia", I think it's safe to assume that they don't find this pleasurable at all.