Real world BDSM is NEVER as extreme, indeed cannot possibly be as extreme, as that featured in the booty calls because regular injuries, even fatalities, would occur amongst individuals visiting such devastating sexual violence upon each other.
Suspending someone by the wrists, full weight, denying them the chance to support themselves using their legs and feet is agonising and has been used historically, all too frequently, by armed forces to extract information from the enemy. No person who knows anything about BDSM and/or anatomy could possibly believe that the Heather character would have consented to be strung up and suspended in such a fashion, or, even if she had consented, which would have been completely out of character, could have endured harsh excruciation like that for a second. Additionally it made absolutely no sense whatsoever for the MC to suddenly start behaving like that, with no intermediate steps towards such behaviour, to all of the girls/women he had become intimate with and had always treated gently and respectively beforehand.
Obviously you have led a sheltered life and are not speaking from experience since much of what you wrote was irrelevant in respect to the booty calls. For instance: You mention "consent" and "safe words". Where did any of the female characters in the booty calls consent to be mistreated anywhere in the game? When did they reveal the "safe words" they were going to use to cease participating masochistically to the MC any time in the game? I saw no evidence of the "normal" BDSM etiquette you mention in any of the booty calls only female character suffering extreme sexual violence.
The BDSM booty calls were ugly, completely out of place, and the MC instantly and incongruously abusive.
That's my opinion, stated from the heart, and if you or anybody else reading these words don't like it too bad. I have never ill treated a girl of woman nor suffered to stand by while a girl of woman was in danger of being ill treated in my presence, nor fantasised about it, been turned on by it, in real life or elsewhere, and feel sorry for those that are.