Congratulations for figuring stuff out.
Regarding the obsession with Anime, if you haven't already, try using it as part of a "reward" system. I know there is more to his inability to complete work than just motivation, but it's still worth a try to tap into that motivation.
Ex: he gets an hour to complete an assignment (or part of one) if he gets it done in less time, the rest he can spend on Anime until the next "assignment time" I know, it's a total been there done that kind of thing with autism, but I find that sometimes I have to reword/present it in a different way to have it click into son's head. Maybe revisit the "old way" that I had stopped using because it stopped working, but now it seems to work again.
Best of luck to you both.
