I think you guys need to check out Digital Devil Saga 1 & 2. The two parts of the series contain almost everything Destai mentioned, and then some. It is also an M rated game, with an awesome mature story. GREAT voice acting too.

Shin Megami Tensei: Nocturne, by the same company, also has a sweet, mature story that I throughly enjoyed.

Both are for the PS2.

The links in my sig are to RP sites based on said games, no websites with information on the games or anything.