The interviews led eight of the women to report the man to police, according to the newspaper Sundsvalls Tidning.
“Stone the bastard,” said a 22-year old who was taken in by the phony researcher and revealed details about her sexuality during puberty.
In addition to posing questions about women's sex lives, the man on several occasions also offered lessons on masturbation.
He asked the women to take of their clothes and follow his instructions.
Police have no leads, as the man made his calls from a protected telephone number.