Gantz

Plot (From Wikipedia):
A pair of high school students, Kei Kurono and Masaru Kato, are seemingly run over by a subway train, after saving the life of a homeless drunk who had fallen onto the tracks. Following their untimely deaths, Kurono and Kato find themselves transported—alive and well—along with a number of people who have also just died, to the interior of an unfurnished Tokyo condominium from which the Tokyo Tower may be seen—and none of them are able to leave. At one end of the room is a featureless black sphere known as "Gantz". By way of green text that appears on the surface of the sphere, Gantz informs those present that their lives have ended. The following words appear on the black sphere's surface: "Your lives have ended. What you do with your new lives is entirely up to me. That's the theory, anyway."

Without explaining anything to them, the Gantz sphere opens up to reveal a bald man on life support in the center, and three racks that offer various items for them to use. Information on the Gantz Targets appear on the surface of the sphere, shortly before the Gantz Team are transported to the location of the mission, where they are expected to kill aliens. Gantz gives out individual suits for each person there, giving them great strength, speed, jumping ability, and protection from harm. Additional weapons and items are gained from the hundred point menu.

The hunters cannot return from their mission until all enemies have been killed, or the time limit has run out. If the mission is successful, each individual is awarded points for the aliens they have killed. They are then allowed to leave, and live their lives as they see fit until Gantz summons them back again for the next mission. The only way to stop having to participate in the missions is to earn one hundred points, and choose the option to be freed. While in the anime version, there are four targets, including a "Kurono alien", at present, there have been nine different types of alien targets in the manga.

My Thoughts:
I heard that this was a very popular series in Japan so I decided to watch this. This is one of those anime that I think you may need to read the manga first before you understand what is going on in the series.

The story is pretty good and the anime was pretty good. There were some "hentai"-ish moments but it was ok. It was part of the story since the main character is a perv! hahaha. It got kinda confusing for me but I still enjoyed watching the series. This is definitely more for adults. I will give this a 3 out of 5. Like I said, there is some background of the story that you need to read in the manga for you to understand it.