Today's appearance at Hutt Valley District Court was in relation to the new charges.
Detective Sergeant Christiaan Barnard said Stewart allegedly used at least three different Facebook profiles to contact his victims.
"We believe there may still be other victims who have been in contact with Stewart," he said.
"In addition to the original profile used of 'Nick Davis', we have found two others which are 'Cee Jay' and 'Cam Jackson'. Both profiles were used late last year and earlier this year."
Anyone concerned about Stewart's activities should contact Hutt Valley Police on (04) 560 2600. Those with information have also been asked to ring through.
Alternatively, police can be contacted anonymously Crimestoppers on 0800 555 111.
No plea was entered for the new charges, police said.
Stewart is due to appear in the High Court at Wellington next week. His next appearance at Hutt Valley District Court has been scheduled for September 10.