Kali is just one form of the Hindu Great Goddess. Her main form of Parvati. All those Goddesses, Kali, Durga, Parvati, are the same Goddess, just different forms of her. She is the consort of Lord Shiva. Lord Shiva is the Hindu Great God, same God as the Horned God, just minus the horns.
The Great Goddess in Hinduism, Maha-Devi, has very very many forms, even some really obscure forms just local to some areas (that most people won’t even know about except those of that area).
Also she has many Tantric forms too. Tantra is the Hindu word for Witchcraft. The mistaken western ideas, that Tantra is some form of sexual spiritual ritual, is not what Tantra means in it’s eastern meaning. Just like modern Witchcraft can include sexual rituals (The Great Rite and sex magick), it is only a small part of what Witchcraft is. Tantra also can include sex magick, but it just a tiny part of what Tantra is, the same as for Witchcraft. So to call Tantra sex spirituality only, is the same as saying that Witchcraft is only sex magick, just simply wrong. The main forms of the Great Goddess (Maha-Devi) that are called upon in Tantra practices are either Kali, or Sri Lalita Tripurasundari, but there is many many minor forms of her that are called upon for more specialized purposes. Kali is more of a wrathful form of the Great Goddess, related to destruction of all non-spiritual aspects of the ego, and Lalita is a very sweet and beautiful form of the Great Goddess.
Lalita is a maiden aspect, but she is a very indepth form of the Goddess since she is related to the very mystical system of Tantra called Sri Vidya, which is the metaphysical knowledge of the whole of how the cosmos is structured, sort of like a Hindu version of the Kabballah, only 100 times more complicated! If you have ever seen the Sri Yantra, it is the diagram used for understanding this Sri Vidya. Every point on the Sri Yantra is related to a different form of Maha-Devi, connected to different aspects of reality on a metaphysical level. It is intensely complicated!