A 42-year-old man has been charged with killing a female student who suffocated during a sex-game gone wrong.
Italian prosecutors believe Soter Mule tied Paola Caputo, 24, to another woman while performing a Japanese sado-masochist technique known as "shibari".
The engineer was originally held for murder but authorities in Rome believe Ms Caputo and her friend consented to the game.
Investigators have so far established that the three spent the night drinking and using drugs at a club before Ms Caputo, said to be Mr Soter's long-term girlfriend, suggested going to the car park of the building in a Rome suburb where she worked as a caretaker.
It is alleged the two women were tied tightly together with the same rope. When the unnamed woman fainted, Ms Caputo was suffocated.