Ishara was a consort of Dagon and considered the personification of the oath. She is considered a love goddess, and medicine, and her name means "treaty, binding promise". At some point she bound herself to Dagon - Father of the Deep, and was his primary consort, his Queen, presiding over the Deep Ones, an amphibious humanoid race indigenous to Earth's oceans.
With her influence, the Deep Ones were easily able to expand their breeding into various small coastal and island communities, her powers allowing them to secure to commitment of the people to continued participation. She was worshipped alongside Dagon by some in the Esoteric Order of Dagon, a secret cult based in Innsmouth.
Her followers would were a scorpion to represent her.