Are such things (Maken Ki etc.) even targeted to 13 year olds? Because I think they are shown only on specific channels, and air at midnight or later. It is also illegal to torrent anime in Japan, though you would likely never be caught.

When I was a teenager, I watched Yuyu Hakusho, Rurounikenshin, Grander Musashi, Fushigi Yuugi, and I loved them. I would recommend them in a heart beat to the appropriate watcher. I already thought that boobs flipping about all over the place was retarded. I watched Divergence Eve as a teen and dropped it immediately after seeing the mindless nudity.

If they wanted fap material, there is plenty of pron and hentai to go around. And you don't have to sit through 20 minutes of "story" drivel.