[@Venku]Oh, you can have several, but you have to have a strong emotional connection to whoever you're bonding with.  So you can have a bond with your girlfriend, your pet wolf, a dragon that you work for (if you work for one, which you don't have to) and the guys in your military unit all at the same time.  The problem with having that many is that if your loyalties get split (say your girlfriend wants you to betray your army buddies or she hates your boss) you can lose the emotional connection, and therefore the bond.  This puts a practical limit on the number of bonds because there are only so many beings that you can have that level of a relationship with.

For example, when the Dragons turned on their pets, the bond was broken because they were no longer devoted to protecting their pets and the pets were no longer loyal to them.

Also, the more traits you try and get through a bond, the slower you get them, as your desire is split.  Multiple sources for a trait will increase that speed, though, hence why I had the possible Vampires bond with multiple people that had the same abilities.