The only kind of person that may have done would be someone that either like you but wanted to prank you as a joke. Or someone who was bored and looked at the first person to prank here.
But if we look at this paper, we can cleary see that the person must have been since a short time. Since that, if we look the evidence, the pranker who did that to you must have done this as soon he saw you in the latest page.
This lead to one and only conclusion, mister, the pranker must be...
Blue Hunter Z all along!!
...
...wait a second.
Oh.
I mess up the whole thing, right?
Dang it.