You just don't get it. You can't. If you lived in Tokyo for 5 years like me, then this game makes perfect nutty sense .
The humor will be extremely hard to appreciate unless you speak Japanese and have lived in and loved Tokyo and its popular contemporary culture.
The girls and the things they wear/don't wear and thing things they do and way they move are a pure rendition of what otaku culture in japan loves. Everyone in Japan is secretly otaku anyway.
Granted the game looks like a ps2 port and probably is, but it's campy and fun no less.
If you cannot enjoy this, I can understand. If you have the right background, though, you will not go home empty handed. It is a simple button masher, but one for dudes or chicks who dig chicks and a few brews!