An excerpt from page 29 of Morriban's Guide to Werecreatures: "Most werewolves willingly allow themselves to be shackled in order to prevent harm to those around them, but this is not a foolproof safeguard; there are countless tragic tales that begin and end with rusty chains finally giving way to that bestial strength. One additional method of keeping a werewolf under control is to sate their hunger in other ways, to 'scratch an itch' they cannot, so to speak. To put it bluntly, extended breeding sessions may quell their antisocial behaviors and keep them docile. Some have called the practice risky or foolhardy, but one cannot argue with results."
(In actuality, she penned page 29 herself and left the book open hoping someone would read it. She has absolutely no trouble staying under control, she just likes getting railed by a procession of castle guards every full moon.)