This woman was a formidable mahasiddha, variously described as the sister or consort of Naropa.
She founded the practice known as The Six Yogas of Niguma.
She is a manifestation of the Dakini of primordial Wisdom who, in a female form, wishes to help all beings to attain the highest realisations.
She appeared to Khyoungpo Neldjor and gave to him the six Yogas and 5 teachings. He then became the founder of the Shangpa Kagyü lineage.
Books: