Vepar is the 42nd spirit listed in the Ars Goetia. This demon, which is often perceived by today’s practitioners as female, is said to appear as a mermaid. She rules over the seas and will guide the ships sailing upon it as well as fill them with weaponry and armor. She can make the oceans stormy at the magician’s request. On a smaller but no less destructive level, she can cause wounds in others. At her urging, maggots will breed in these sores and your enemy will die within three days.
Modern occultists such as Ford and Connolly indicate the Vepar can sway the seas of human emotion as well. In particular, she is a good daemon to invoke if you wish to deal with your own toxic emotions. A daemon that can create wounds must have a good understanding of what causes us dis-ease, after all. I’ve had good luck working with her in this context over the last week.
Personally, I see the flow of water in its shape, as well as the belly of a ship heavy with weapons. Three daggers thrust downwards perhaps indicate the toxicity she can cause—and remove.