Marquis Casel El Tiberius (カーゼル侯爵 Kāzeru Kōshaku) is the leader of the Imperial Senate, as well as the Pro-Peace fraction. He later becomes the adopted father of Sherry Tyueli after the noble sacrifice of her parents to ensure their escape from the Oprichnina.
Not much is known about his personality though he speaks as the representative of the Senate bravely. He is also known to have a compassionate side as he worries about his people who suffer in the hands of the Oprichnina.
Having very close ties with the Tyueli clan, Casel becomes sympathetic towards Sherry Tyueli, whose parents sacrificed themselves so that they can escape. He later takes responsibility by adopting Sherry as his daughter.
Casel also approves of Sherry's romantic interest towards Sugawara, who chose to disobey his superior's orders in order to save Sherry from being taken by the Oprichnina.
He is shown to be quite noble and soft-heart, especially with the common citizen since he shows disgust toward the attitude of the Empire in practicing scorched earth tactics. He also wise and far-thinking since he tries his best to stop the suicidal war against the JSDF when the Empire loses more than half of its fighting power.
Casel is a middle aged man with wrinkled face, and short black hair. In the manga, he has longer hair.
Born in the family of baron, he worked his way up to become the leader of the Senate. He would often question the Emperor Molt Sol Augustus's decisions due to his recklessness. After the bombing of the Imperial Senate, Casel is seen again questioning Molt for the unprecedented damage and humiliation that took place.
- His name is based on the second Roman Emperor Tiberius.
His full name is given in Manga chapter 63 page 17 shown in Gallery below, from: http://www.taadd.com/chapter/GateJietaiKarenoChiniteKakuTatakeri63/868331-17.html