Tokko is the story of Ranmaru who joins a group that call them selves Tokko and do their best to destroy the 108 demons that have been coming from another dimension for the last 5 years. They gather the missing pieces of the box that opened the dimension so they can close it and save the human race.
My thought:
This anime was interesting. The storyline does follow from episode to episode, always geared toward killing the head monster. Ranmaru at first wants revenge for his parents death that a monster killed, which leads him to meeting Sakura and the other members of Tokko. I guess the ending is ok if they do a second season, otherwise it truly sucks. If you want to watch an anime that has action, lots blood, and gun and sword use, then watch Tokko.