I thought "milking" was used in orgasm denial as a way of sustaining long-term chastity.
Here's a description quoted from Wikipedia:
"Prostate massage, also known as prostate milking, is sometimes carried out as a medical procedure for the treatment of chronic prostatitis and benign prostatic hyperplasia (BPH), although it is highly inadvisable for patients with acute prostatitis, for whom the infection can spread elsewhere in the body if massage is performed.
Done internally either by finger(s), prostate massager or other medical instrument, prostate massage may result in orgasm without any genital stimulation. It can also be indirectly massaged externally through the perineum, although this may not be effective in the removal of fluid.
No more pressure should be used than for rubbing an eyeball. The procedure is initially undertaken gently using the index finger and a latex glove by massaging the lobes on either side of the prostate, taking care not to rub vigorously on the nerves in the middle.
If the prostate is full and stimulated sexually in some cases it may consciously and voluntarily be contracted, thereby emptying itself in the same way as during ejaculation but with none of the surrounding organs stimulated, without actually squeezing it digitally.
Electroejaculation is a procedure in which nerves are stimulated via an electric probe, which is inserted into the rectum adjacent to the prostate. It is most commonly encountered in animal husbandry for the purpose of collecting samples for testing or breeding. Prostate milking is also encountered as part of sexual activities, particularly involving the use of sexual denial."