Yeah usually in adult men, particularly ones who engage in sports that require strength or other advantages that ahem "stimulants" bring. It happens when excess testosterone in the body gets detected, sensed as too high via homeostasis them converted into excess oestrogen which then proceeds to deposit breast tissue in that area. A feedback loop. Not everyone who juices gets it though and some steroids are much worse for it than others. You can counteract it if you catch it in time with anti-oestrogen breast cancer drugs on cycle but if you don't surgery is basically the only thing that rids it.
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