Villains are ultimately selfish beings, but does this mean that we cannot be loyal? And if a villain is ultimately capable of loyalty, just how would this sentiment manifest itself? Despite what some may think, villains are very capable of loyalty. As a matter of fact, I would argue that a villain's loyalty can be much truer (deeper, more honest and more realistic) than the sorry ideals that pass for loyalty within "goodness" type thought.
Villains are selfish creatures to be sure, but great excess of anything can be harmful and this definitely applies to selfishness. Humans are social creatures and as such we need things from other people from time to time. This especially applies to a villain who wants to gain power. Assuming you don't possess any unbelievably fantastic abilities (superpowers), you're most likely going to need occasional assistance of others if you wish to become more powerful (not to mention the fact that any concept of social power or influence becomes somewhat pointless if you don't include other people in the equation). Simply put, there is often power in numbers and this applies to almost any endeavor.
Now, it will be argued that relying on someone because they will help you to achieve your goals, is not true "loyalty". However, realistically, I believe that this is one of the most pure forms that loyalty can take. If you rely on someone for your success or even survival, then obviously that person means a lot to you and what better motivation is there then necessity? And if you do rely on another individual for your prosperity for a sufficient amount of time, then it is almost inevitable that a deeper camaraderie or feelings of respect will surface out of that relationship.
Of course, feelings of loyalty could also easily stem from a purely emotional source. Most likely as a result of love or friendship between two people (and yes, villains are capable of both love and friendship, though they are very selective about it). It shouldn't need to be explained why true feelings of love and friendship might bring on the mind-set of loyalty. However, you may be wondering how a villain (a selfish being) could obtain such an emotion in the first place. A simple answer is that although selfish, villains (at least the ones that this rant is aimed at) are still human. And humans (even dark, greedy, manipulative, antisocial ones) do have a tendency to connect and sympathize with individuals that they see something appealing in. These are the same mechanisms that would cause anyone to have these feelings and attitudes towards another individual.
Villains can be some of the most complex and multifaceted characters in fiction, so it should come as no surprise that their real life human equivalents are capable of much more than just one dimensional "evil". The truth is that villains believe in doing things their own way and so they rely on their own selectivity and taste to determine who is worthy of their loyalty or anything else. They are also responsible enough to do this in an intelligent and discriminating manner. They rely on their own judgment and don't need any other source to tell them what they are "supposed to do". The fact that villains are so proactive in choosing where our loyalty lies, makes that designation much more powerful, as well as more significant.
One of the most revolting things about the goodness mentality is the simple lack of individual loyalty that it embraces. Basically, to be "good" (as that term is usually understood), means to be loyal to a worthless and abstract principle as opposed to being loyal to flesh and blood people (yourself included). The fact that someone would choose to serve general concepts of right and wrong over themselves and other individuals who they (claim to) care for, just sickens me to no end. Large scale principles do not matter. Who cares if it's right or wrong as long as it serves your individual purposes? And the hypocrisy! The idea that someone would actually betray a person that they care about just to "do the right thing". If there was some personal benefit to this betrayal, then I could see that. But for a principle?! How repulsive.
This is one reason why I believe that tendencies like selfishness and moral flexibility help to breed individual loyalty. If a person is unable to put aside their ideas about right and wrong to serve themselves, then there is little chance that they will be able to do it for anyone else. On top of that, many of these "goodness" embracing individuals claim to love everyone. As I mentioned towards the end of my "Hate: An Underappreciated Emotion" rant, trying to love everyone is not realistic and makes it much harder to determine who you truly love. It waters down your interpretation of the emotion to the point in which it becomes worthless and makes it more difficult to truly love anything. Love is only worth something if it is used properly and if it is overused, then it ceases to function way that it is intended to. I think I can safely say that love, like loyalty, should never be used indiscriminately and is never unconditional. As villains, we must strive to be more discriminating with our affections. If the only reason that you care for someone or something, is that you're "supposed to", then you have no good reason and therefore cannot be trusted.
The rule here is: practicality over principle. If a villain's loyalty lies with individuals that are useful to them and that they have positive emotions towards; then it follows that they would possess no loyalty towards those who they consider worthless and people that they dislike or despise. This does not mean that you can't feign loyalty towards a person whom you might find fairly repulsive, but who is temporarily valuable to you; playing along with them until they've outlived their usefulness (you can always "stab them in the back" later; figuratively or literally, your choice). Deception and betrayal are both acceptable activities for a villain, after all. But make sure that you carefully weigh the pros and cons before engaging in such a betrayal. Remember that you should never make an enemy of someone until you're sure that you can afford to (also remember that anyone who has ever accomplished anything of value has picked up some enemies along the way).
Perhaps even more significant, is the idea that a villain should never remain loyal to someone or, especially, lots of some ones, on the basis that it is expected of him. This especially applies to socially common objects of loyalty such as family and patriotism. To be loyal to anything, out of the sheer principle of the thing is ridiculous. If you see no value in these concepts besides catering to the social expectations of others, then you should just say "screw this, I'm doing things my way". A villain has no problem committing social taboos in the name of their own personal interest (what will they do, accuse you of being "evil"?). And from a Machiavellian standpoint, betraying (or doing worse) to a family member that you don't particularly like, can have a very demoralizing effect on other potential enemies (as in: "if he'd do something like that to his own flesh and blood, what would he be willing to do to me?"). I say if they're dumb enough to give you an excuse, take advantage of it, family or not.
Despite our capacity for treachery, villains can be fiercely loyal. Those who we hold in esteem are worth more to us than most other humans on earth put together. It is not completely out of the question for a villain to sacrifice themselves to save someone they care about. However, it should be noted that even this is an act of selfishness in that the villain would rather not continue living in a world without this person; in this particular situation. The most important element here is the ability to determine who is worthy of your loyalty and who is not. This kind of deliberation is rare among the masses of people. It requires the ability to separate, classify, and judge others by various standards. And who is best suited to determine the standards by which these individuals should be judged and to carryout this sorting of people accordingly? Why you of course! After all, you are the most important individual you will ever know. Ultimately, there's only one person in this entire universe who is truly worthy of your unconditional loyalty.