Sei Sakuraoka

Sei is confident, sexually direct and comfortable making decisions without worrying much about social convention. Kurono's request to have sex surprises her less than it might most newcomers, and she agrees because she finds him attractive.

She is also compassionate and emotionally perceptive. Kurono's vulnerability does not repel her, and his behavior during the mission gradually gives her reasons to take him more seriously than their initial physical encounter suggests.

Sei is courageous in combat. Her confidence in her martial arts is genuine, and she willingly joins fights to protect other participants instead of remaining hidden from the mission targets.

Sei is an accomplished martial artist even before receiving Gantz equipment. She has competed in underground fighting and possesses substantial close-combat experience.

The Gantz suit dramatically enhances her existing physical abilities, increasing her strength, speed and durability. This combination makes her much more effective in close combat than most first-time participants.

She also adapts to Gantz's weapons and fights alongside the more experienced hunters during the Buddhist Temple mission, although martial arts remain the foundation of her combat ability.

Sei enters Gantz with the large group of newcomers before the Buddhist Temple mission. After Kurono explains the importance of the suit, she follows his advice and equips it, immediately giving herself a better chance of surviving than many of the other first-time participants.

Her initial sexual encounter with Kurono develops into genuine attraction as she watches him fight. She eventually asks whether he will become her boyfriend and talks about taking him for a drive after they return.

During the final stages of the Buddhist Temple mission, Sei realizes that Kurono remains emotionally attached to Kishimoto. Even so, she continues fighting beside him and ultimately sacrifices herself while protecting him from the temple aliens.

Kei Kurono is Sei's principal personal connection during her time in Gantz. She initially sleeps with Kei Kurono because she finds him attractive, then develops stronger feelings after seeing his courage during the mission.

Kei Kishimoto becomes important to Sei's understanding of Kurono's feelings. Sei recognizes that Kurono remains more emotionally attached to Kishimoto than he is to her.

Masaru Katou is one of the experienced hunters attempting to guide the newcomers through the Buddhist Temple mission.

Juzo Togo and Musou Tokugawa are among the other first-time participants drawn into the same mission.