The 19-year-old cannot be identified because he was a minor at the time of the offence in the fall of 2011. The victim's name is also protected.
A second charge of distributing child pornography was withdrawn.
The man will be sentenced on a later date.
Another 20-year-old man was also charged, and got a conditional discharge earlier this month after he pleaded guilty to making child pornography.
An agreed statement of facts delivered in that man's case in September said he took a photograph of another male youth who smiled and gave a thumbs-up while having sex with a 15-year-old girl, who was vomiting out a window.
In reading the agreed statement of facts into the court record, the Crown said the girl was not aware that the picture was being taken and did not give consent to it.
The Crown also said the man in that case told police he sent the photo to the male youth, who had sex with the girl, and he is not alleged to have sent it to anyone else.