Oita Saikyou no Shuujin wa Kyou mo Ikinokoru

"The strongest old prisoner survives today."

The prison "Solitary" is said to be the worst prison in the universe. It is a living hell where thousands of people lose their lives every day. Among them, there was only one prisoner who survived for 64 years. The man's name was Argel Lastos. His rank is only first class, which is not particularly high, but he has survived numerous deadly battles with high-ranking prisoners and continues to survive. In order to maintain his aging body, he makes a secret contract with the prison's designer, Karaisman, and keeps himself alive every day. The mission he is given this time is to protect a little boy.

Set in a brutal prison, this is a story of survival by the strongest old man, depicted on an unprecedented scale. A sci-fi dark fantasy action story full of blood and ingenuity begins now.

(Source: Piccoma, translated)