Actually, there is no "god" of Tantra. No god or goddess, no deity at all. Any deity that we infer or impute is because we Westerners have a predisposition to superimpose our understanding of the universe on every other culture and religion past or present.

On the other hand it would seem that there are hundreds of gods and goddesses in Hinduism, though you have to dispense with your predispositions in order to understand these energies. The life energy expresses itself in many forms, these forms are all godlike and powerful expressions in the universe. Each god and goddess in the Hindu philosophy is a metaphor for a different way that this energy is expressed.

Simple that, nothing more, nothing less.

Here is what Tantra teaches:

You are the source of the life energy. When you wake up to this reality you realize that what you always thought god was is what you really are! You have the opportunity to express that god energy into the world, or not. If you do express that energy, god exists in this world. If you do not, god does not exist.