How does William Dalrymple explain Tantra?

Tarapith has a tale, a tale of Tantra, cosmic powers and not to forget secret orgy. In Tarapth, the dead body or shab, when not cremated is buried underground. The woman is considered to be both Masturbator for her male partner as well as for her own self. It is believed neither the female form nor the male form could tolerate the secretion of the semen and only the Tantrika reserves the right to taste the semen released from her vagina.

This is a practice that wholly subverts the Brahmanic culture by worshipping the dead. In essence, Kaula Tantra or the practice of Kaya or body known as Kaya Sadhan, is left handed, where the Tantrika is the hero and her female consort is her sexual coitus partner. Masturbation is practiced with the ejection of semen restrained to the limit that it does not become sticky for the woman. Here the dead body is worshipped as Shab or the impure dead. No one is allowed to roam the burning place and cremation ground with shoes on. The practice of Panchamakara or the five ‘M’ -- madya, mangsha, matsya, mudra and maithuna is practiced. It is performed on a full moon night on the altar of Panchamundi, that symbolize control of five senses --- chokshu, karna, nasika, jihva and tvak. The practice is analogous to and a contemporary of Vedic practice, though the Vedic Brahmins subscribed to the mental Tantrikas, who looked into the body. Tarapith is the seat of severe clash between two opposing schools of thought - the Brahmins vs the lower caste sub-alterns. Tarapith is now more of a millenium park and less of Tara, the manifestation of the Hindu pantheistic Dasha Mahavidya.

(For further reference: THE TWILIGHT LADY IN NINE LIVES: WILLIAM DALRYMPLE)