While a decent game in it's own right, the best adjective for eternal poison is: 'bland'.
Eternal Poison has a relatively simple premise: Demons have entered the Kingdom of man and stole the princess of a rather powerful kingdom, enter the various interest groups who wish to turn the situation to their advantage ranging from the zealous Ashley to the mysterious Thage. Unfortunately I have not had the chance to play through the entire game to attain a full grasp of the storyline, however from what i've seen so far I was not witnessing anything groundbreaking in terms of plot.
That being said, the core of my review will fall to the aspect of Gameplay. The gameplay consists of the standard turn-based chess-esque fare. If you think Final Fantasy Tactics or, as one other reviewer mentioned, Stella Deus, then you have a basic understanding of what the game play is like.
The game's attempt to differentiate itself lies in the enemies which you are fighting: the majin. The majin, your natural enemy, can be captured and used for your personal devices, first you must bind them by inflicting a certain amount of damage past their HP. After they are bound they can be captured by a player character. Captured majin can be either sacrificed to earn money, new skills, or Poison Points which are used for the second purpose of majin; majin can be summoned in battle. Beyond that, and the usual elemental/physical attack affinity the game offers little in the way of significant complexity. There is one side game which involves a checker's like puzzle game which while fun, is nothing spectacular.
The graphics are, once again, nothing to write home about. The battle screen is rather poorly rendered, reminding me somewhat of stella deus (I had a bad experience with that game, lasting little past the first battle). The attacks are fully animated, and the characters are well rendered, however it's nothing too impressive, and gets repetitive. All in all, mediocre.
The sound is rather nice, with classical tracks mixed in with a gothic feel. Overall it is pleasing to listen to while you play.
In conclusion, the game is rather bland in it's delivery, and while by no means a 'bad' game it is neither a 'good' one. I would definitely hold out until it hits the used section before buying because I can't justify the 40 dollars I spent on it. If you want a good RPG to pass your time hold out for some of Atlus's other games coming out.
Overall: 7.5 magically enslaved demon wolves / 10