I was surprised to see the second game in this series have such a strong debut in the 10/19 Japan preview, especially considering it was a series of which I had never before heard.  I did a little digging and found a couple of screenshots, and was really intrigued by the game's style.

Although some accounts differ, the premise of the game seems to be that the player has somehow come into possession of a monster; instead of the expected response, he actually likes the monster and wants to protect it by hiding it beneath his home.  As the player, you are tasked with creating a dungeon beneath the home to provide safety for this monster, doing so by digging pathways and breeding various creatures to do battle with a continuous stream of heroes who have apparently heard tell of your charge and seek to capture and/or kill it.  There are creatures of both physical and magical prowess, and there is a sort of "monster ecosystem" that develops in which monsters regularly consume each other for food in order to survive and reproduce.

Further intrigued, I decided to "borrow" a copy of this game from the interwebs to see if it was actually playable despite the language barrier.  Little did I expect to find one of the most addictive games I've ever played, even though I understand almost no Japanese.

This game needs to be translated into English.  It deserves it.  Apparently there was a listing of an English title for the sequel at TGS, called "Destroy All Heroes 2."  However, this may have been only hearsay and certainly affords no proof of a planned release outside of Japan.

Even if Sony passes on localizing these games, I hope some other enterprising publisher will see fit to translate them (Atlus?  Please?).  The games are unique and fiendishly addictive, and the sequel seems to have taken the base concept and expanded upon it significantly.  There is some sort of multiplayer as well, though I have no idea how it works.

In conclusion, Yuusha no Kuse ni Namaikida, and its sequel, are worthy of attention.  Keep an eye out for them.

the game system seems really intriguing and fun

It is surprisingly awesome.  Once I learned a bit about the mechanics, I was hooked.

You will learn of this game and be enlightened! I command it!

Yeah, it's an excellent idea from SCEJ. I always wanted to be the bad guy. (not choice wise like Fable, Oblivion, etc.

Might I direct you to:

*Overlord
*Dungeon Keeper (series)
*Deception (series, minus the last one)

For starters...

Overlord wasn't fun at all.

To be honest that looks interesting.