A different and intriguing (although much more complex) form of interaction between sub is empathy. Whether you are involved in different sub Dom a joint session, but not competitive, whether they are both subjected to the same Sun, when the conflict is not their relationship is full of topics of interest. Sharing a session painful and humiliating (and even more share the person who owns their soul) is born in sub feelings that give the impression of being strong and sincere. Obviously I can not speak from personal experience, but only with the spirit of observation of those who see and try to understand. I noticed that for some types of the sub does not feel "alone" in front of your Dominant, rightly perceived as unattainable and impossible to satisfy in full, makes the task less difficult to kneel and serve.
Not being a philosopher, I do not like debating these matters so much to do, but always and only groped to take all possible pleasure for me to find new ways of humiliation and suffering for my puppies. So I noted that this form of brotherhood can be submitted profiqua exploited for the two games where, instead of being in competition, they must "share".
What do I mean to share? Must essentially divide in an alternative punishment to endure it, but they must be to say "enough" and go through another. A few examples: the two submitted with each clamp labia (or nipples, the concept is the same). Weights are only on one, when it can no longer pass each other, or both on all fours and the first hit on Sun with the barrel and when it says that suffering is too much, continue with the other. You can invent dozens of different situations.
Apparently you might consider watching a game like "buck", but it often happens that both bear more than they would normally, but decrease the suffering of another. Funny.