Kiznaiver

Kiznaiver is an original anime series that aired in 2016.

The story takes place in Sugomori City, a seemingly normal town that was actually created to test a large-scale experiment known as the Kizna System, which connects people through shared pain and suffering, both physical and emotional in an attempt to create world peace. Those who are connected to the system are called "Kiznaivers".

A few days before the start of summer vacation, a mysterious girl named Noriko Sonozaki tells high school student Katsuhira Agata and several of his classmates that they have been selected to become Kiznaivers.

Episode 1
Katsuhira's shirt flies up as he falls down the stairs.

Episode 7
Tenga takes his shirt off before heading in for a shower.

Episode 9
Noriko unbuttons Katsuhira's shirt to see what is causing him pain.

Episode 10
Katsuhira unbuttons his shirt to reveal that his scar has vanished.

Episode 12
Yoshizawa and Kamaishi return only to get beaten up again.