If you liked Bubble Bobble, you will LOVE this one. I have played and completed both, and I can say without a doubt, this game beats Bubble Bobble! It is AMAZING.
The graphics are beautiful and charming, lots of cutscenes and the voice acting although Japanese only is superb. Power ups really make a difference and are fun to grab and use. 6 different stages with 10 levels, and each world has their own boss and unique enemies. The bosses are at times very challenging, but even if you're beat you always want to keep on going. Unlike Bubble Bobble, each stage also has different and good music, makes the game so much more tolerable and enjoyable. Stage 6 has very impressive backgrounds and music, and the final boss fight is awesome. Plenty of Credits and chances to keep going where you were when you lose all your lives. Plenty of options and they even added a few extra bonuses with the voice actors. The package as a whole is seriously well made!!
Ignore the haters bashing the game because of the young girls. Yes, they are at times almost going a bit over the edge when showing them off. But it's a Japanese anime game on an anime/hentai based system. If you watch anime and have already seen magical girls transform into their powers, you won't find anything surprising here. Once you get over this, you will be greeted with probably the best game the system has to offer, and a seriously VERY good game at that. The only real problem is that it's stuck on the PC-FX and nothing else, so unless you emulate or are against piracy (PC-FX has no disc copy protection...) you have to hunt down an original copy which is very expensive now.
Arcade and Bubble Bobble lovers just have to play it. Underated is an understatement, it truly is an amazingly well made game!