Wallenstein

Wallenstein, also known as the one armed swordsman, was an apostle for the terrorist organization Rebellion, and was also the mentor of Nagi Arisuin.

Personality
A very hardened individual, Wallenstein believed that there was no love in the world and that anyone who thought there was such was foolish.

Wallenstein has shown to be a very cruel individual wanting to punish Nagi before killing him, by killing the very person Nagi has taken to ashis sister. Wallenstein was also a sociopath as he took lives without much remorse or care.

History
Wallenstein was hired by a mayor of the town Nagi was leaving at as an orphan. After Nagi was able to kill all the gang members, before him. Wallenstein then introduces himself to Nagi and gives Nagi a gift, showing Nagi the severed head of the mayor to him. Wallenstein then persuades Nagi to join him and his organization but only after Wallenstein paid Nagi a ridiculous amount of money first. Under Wallenstein's tutelage Nagi had become a merciless assassin, killing any person Wallenstein had asked him to kill.

Akatsuki Strikes
Wallenstein was first formally seen at Akatsuki academy, when he began to interrogate on the reasons why Nagi would betray him. After learning Nagi's reasoning, was because he cared about someone, Wallenstein had become angered and then decided to punish Nagi before killing him by killing the very person he cared for the most, Shizuku, who had just arrived.

Wallenstein was able to over power Shizuku during his fight with her, being able to nullify all of her attacks, do to his friction manipulation ability. However, Wallenstein is eventually defeated by Shizuku, by making her own body into water, and using the very air Wallenstein was breathing to drown him.

Abilities
Friction Manipulation: Wallenstein has the ability to manipulate friction being able to nullify all physical attacks. He can also use it to steadily walk on ice without much problems.

Device
Sword: Wallenstein was shown to have a sword as a device, which he could over power many foes with, without much effort.