A form of tantric sex.

Mr. Gurdjieff, even into his sixties, had a very
active sexual life, so much so that a student
who lived in the living room of his apartment,
had to move out, he could not take the nightly
noisy "disturbances", coming from the next room,
as a parade of attractive women arrived each evening.
Somewhere once, we found a reference that a young
woman, part one of his lovers, vaguely stated that he
practiced a form of tantric sex.