Um, the rule of thumb about this sort of porn is that the underage must looks *unrealisitc" in order to pass the law. The Japanese certainly has its own sort of laws and loopholes.
I am not sure what to say; great art. It should be classified as Loli. Just because the pedo dipicted here is a female does not change the fact that the child has been groomed. Yes, I have my fair share of reading porn....I just wonder why this piece is on the website. However, no matter how you look at it. it is also a Yuri.
Since this is fiction, you can just imagine the story is set in a world in which children are not like our children, their brains are advanced and they are capable of goal-driven sexual behaviour, that way you can also imagine that this child /hasnt/ been groomed. Sometimes it's impossible to do this, particularly if you're a csa, or if you've a personal close story with the subject, but it sure does help to enjoy works like this when that's not the case.
It's important to remember that only you can oversee, approve of and change your own personal interactions and dynamics with fictions, and no one can judge you for your inner thought processes, specially fantasies.
