Uterine stimulation. It's byproduct of ero-artists imagination by the same logic that pounding the cervix feels good for the woman.
Idk about massages, and pounding one's cervix will only lead to a trip to the nearest hospital. However, deeper stimulation, which can only be achieved with significantly longer penis/toy will lead to MUCH more intense and lasting orgasms. The cervix thing is more of a misunderstanding than a straight up lie.
Haha lol
This is super cool!This is bad!
This is bad!!Wh- what is this..?♥Th- this... is ridiculous...Ah... stop... don't!
I'm cumming♥
I'm cumming... I'm cumming♥