Vijnana Bhairava Tantra
66: O Gazzelle-Eyed one, by the employment of magic, supreme delight arises in the heart of the spectator instantaneously. In this condition of the mind, Reality manifests itself.
67: When by stopping the opening of all the senses the current of all sensory activity is stopped, the pranasakti moves slowly upward, then in the upward movement of pranasakti, there is felt a tingling sensation like the one created by the movement of an ant (over the body). At the moment of that sensation, there ensues supreme delight.
68: One should throw or concentrate the delightful citta in the middle of vahni and visa bothways whether by itself or permeated by vayu (pranic breath), one would then be joined to the bliss of sexual union.
69: At the time of sexual intercourse with a woman, an absorption into her is brought about by excitement, and the final delight that ensues at orgasm betokens the delight of Brahman. This delight is in reality that of one's own Self.
70: O Goddess, even in the absence of a woman, there is a flood of delight, simply by the intensity of the memory of sexual pleasure in the form of kissing, embracing, pressing, etc.