BESM is a good system for playing any genre. You can't go wrong with either 2nd or 3rd edition. It is heavily-adorned with anime flair; the characters are mostly better-than-average humans. If you want to play gritty humanoids with many quirks and faults, then BESM is not that type of game. So, for 8 dollars, if you bought BESM rules, then this supplement is OK to purchase. While it gives you some interesting ideas for dungeon-crawling anime action, most of the book is tied into the story-line of Lysandra and the sample dungeon.
If you decide to get this game, make a decision on paper or PDF first, and be happy with the one copy you have.