You must understand that it is difficult to describe how a prostate massage feels, even more difficult to take a picture of it! Mistress Harley has had clients ejaculate from the sensation.
The most reported 'side effect' goes like this, "Mistress, I have to pee! I have to pee RIGHT NOW!" But, 9 times out of 10, when placed in front of a toilet, with the prostate massage continuing, there will be no pee. None. Instead, there is pre-cum.
To better understand, please take a look at the photo below...