A blood exchange between a human and a vampire results in a blood bond with that vampire. This can mean different things for different species of vampire.
Ugentas Blood Bond
The Ugenta vampire will be able to sense the human's thoughts and emotions, knowing if that human is in harm or distress - for eternity.
The human will also experience sexual dreams about that vampire.
The older the vampire, the stronger the bond.
The more times blood is consumed from each other, the stronger the bond. It will also increase the likelihood that the bond will develop into emotional attachments or enhance emotional attachments already there.
Other Species and Blood Bonds
An exchange between a human and another species of vampire must be made within a short time. Depending on the affections for one another, it can serve as a form of intimacy - much like sex, in the way that it can be just for fun or a way to show attachments. If it is just for fun, it is usually done to get the human high on V . If it is for intimacy, the more it is done, the more likely it is that a small psychic bond could form, much like the Ugentas. For Daevas, for instance, it will be easier to do tricks with compulsion, like telepathy.