Gantz: Second Stage is a tV series anime that premiered in summer 2004, produced by GONZO.

About the production: the story comes from a manga, there are 13 episodes of about 23 minutes and its current status is "finished".

Its main genres are action, drama, ecchi, horror, psychological, sci-fi and supernatural, with themes such as Death Game, Aliens, Body Horror and Gore.

On AniList, Gantz: Second Stage has an average score of 65%, a good score, and appears on 27,706 users' lists.

The franchise continues in or follows from: GANTZ.

Kurono Kei and his ex-elementary school classmate, Kato Masaru have survived the first two ordeals that the unknown black sphere Gantz has sent them through. Exploding body parts, struggling to stay alive till the last seconds and seeing your fellow comrades fall in a pile of blood and gore are norm to them now. They are aware now that Gantz can call them up along with any new deeds, at any time for another confrontation with aliens. Will Kato's experiences in the Gantz world give him the same courage in the real world? With fellow veteran Gantzer Kei Kishimoto currently staying at Kurono's home as his "adopted pet", can Kurono stave off his growing lust for her mammaries? What the heck is Gantz? (Source: anime-source.com)

Official synopsis from AniList.