Both of them, still, in some places, although she may get more lenient treatment because she's a juvenile. Other places have cleaned that up in various ways, although I think he's usually still at risk unless he actively turns her in to the Authorities(TM) for sending the picture.

And there's a subset of crusaders (not all of them, admittedly) who will say, with a straight face, that there is abuse involved. To wit, she abused herself by creating and sending the image, and he abused her either by giving her the idea, or by looking at it.