Music played during the climactic orgy of Claude Pierson's supernatural oddity from 1977, 'Le Délire Des Sens.' The music score also includes piano music of Erik Satie, and this particular track must have been sourced. Pierson used the same track again in 'Vierges Et Débauchées', 1980. If anyone can identify it, please let me know!
UPDATE - I've since been informed it is Pierre Porte - Ganymede