SCP Foundation Iris Through the Looking Glass (Light Novel) Vol. 1

An ordinary boy encounters the paranormal when a photo of the same girl starts inexplicably showing up in every book he opens. One day, the girl reaches out and pulls him into the photo to her location: a cell in a top-secret facility belonging to the SCP Foundation, an organization dedicated to the research and containment of people, objects and phenomena that defy reality Even worse: they've deemed him a threat to be contained, and he's going to have to work with them if he ever wants to see the outside world again