|Details from a tankha of Khyungpo Naljor, Eastern Tibet, circa 1900, courtesy of Buddhist Artefacts / Parkham Place Gallery, Sydney, Australia|
Niguma received a transmission of the four complete empowerments of tantra directly from Buddha Vajradhara. Her instructions form the corpus of the Shangpa meditation practices, and today, three-year retreats offered at Kalu Rinpoche centers around the world include the Six Yogas of Niguma. Niguma was Naropa's sister, or perhaps his wife. We don't know the exact relationship between them because the Tibetan text employs the term lcam mo which can mean either sister or wife.
Sukhasiddhi, the other dakini in the lineage, is always presented as peaceful, beautiful, and ripe with blessings that she continually bestows on the lineage. She was banished from her home at age fifty-nine, became a beer merchant, and received teachings from the adept Virupa.
The founder of the Shangpa lineage, the yogi Khyungpo Naljor, names both women as two of his four root Lamas.
The dakini, female and playful--although sometimes wrathful--is emblematic of the tantric view of reality. When Khyungpo Naljor meets with the lion-faced dakini Singhamukha, for example, she tells him, "The supreme instruction is / To recognize the dakini as your own mind."
The stories of Niguma and Sukhasiddhi are the first biographies in the book Like an Illusion: Lives of the Shangpa Kagyu Masters. Details on the book are available here.