Kikunojou Tendou is the current head of the Tendou family, as well as Kisara Tendou's grandfather. 

The Gastrea virus spreads like wildfire, causing each infected host to rapidly mutate, gaining new powers and abilities with every stage of development, even while they continue to attack, kill and infect multiple new hosts. Unable to fight a pandemic enemy that turns defenders into adversaries, the shocked remnants of the human race are forced to retreat into cities surrounded by giant monoliths made of Varanium, one of the few materials that can stop the Gastrea. Now mankind's last hope lies in the Cursed Children: young girls infected with the virus who have managed to retain a hold on their humanity. Paired with a partner, they alone have the strength to take on a Gastrea in one-on-one combat. But the very thing that gives them power is a ticking time bomb, so even as they protect humanity, they are also feared and shunned. Are they Girls? Monsters? Or Mankind's Ultimate Salvation? 
 
(Source: Sentai Filmworks)

Tamio Ooki was a Japanese voice actor. He was affiliated with Mausu Promotion.

The future–where a terrible battle against a parasitic virus called “Gastrea” has been fought, and lost. Humanity is cornered, and lives in despair. Rentaro and Enju face constant danger in their work as a team anti-Gastrea specialists known as “Civil Security.” If the daily fight against oblivion weren’t enough, they’ll soon face a threat that could destroy all of Tokyo…
 
(Source: Yen Press)

A near future, where humans have been defeated by the viral parasites named Gastrea. They have been exiled into a small territory and live in despair, side by side with terror. 
In this world trapped in darkness&mdash; 
Rentaro, a boy living near Tokyo and member of the "Civil Security" &ndash; an organization specializing in fighting against the Gastrea &ndash; is used to accomplishing dangerous tasks. His partner is Enju, a precocious young girl. They fight thanks to their peculiar powers until one day, when they receive a special assignment from the government. This top secret mission is to prevent the destruction of Tokyo... 
Set in a near future, this thrilling heroic-action story... starts now! 
(Source: Baka-Tsuki)