Kali is the Hindu goddess of death, time, and doomsday. She is often associated with sexuality and violence but is also considered a strong mother figure and symbol of motherly love. Kali embodies shakti – feminine energy, creativity and fertility – and is an incarnation of Parvati, wife of the great Hindu god Shiva.
 
Kali  is particularly worshipped in eastern and southern India and specifically in Assam, Kerala, Kashmir, Bengal – where she is now worshipped in the yearly festival of Kali Puja held on the night of a new moon – and in the Kalighat Temple in the city of Calcutta.
 
"Although depicted in many forms throughout South Asia (and now much of the world), Kali is most often characterized as black or blue, partially or completely naked, with a long lolling tongue, multiple arms, a skirt or girdle of human arms, a necklace of decapitated heads, and a decapitated head in one of her hands. She is often portrayed standing or dancing on her husband, the god Shiva, who lies prostrate beneath her. Many of those portrayals depict her sticking out her tongue, which is sometimes said to indicate her surprise and embarrassment at discovering that she is trampling on her husband. Yet the association of Kali with an extended tongue has early roots. A precursor of Kali is the ogress Long Tongue, who licks up oblations in the ancient Sanskrit texts known as the Brahmanas. The Devi Mahatmya tells of Kali springing from the anger of the goddess Durga to slay the demon Raktabija (“Blood-Seed”). During the struggle a new demon emerges from each drop of Raktabija’s blood as it hits the ground; to prevent this, Kali laps up the blood before it can reach the ground."
-www.britannica.com/topic/Kali