** First is the prison doctor Sasaki. Sasaki hides behind the veneer of a kindly old man but [[BitchInSheepsClothing in reality, he is a cruel sadist who regularly rapes attractive male prisoners.]] Sasaki coerces them by holding privileges and favors over their heads. One prisoner is eventually DrivenToSuicide thanks to Sasaki's molestations. Sasaki schemes with the warden Ishihara to murder anyone who knows the truth and after leaving behind the prison, continues molesting young boys when conducting a political campaign.
** Sasaki's partner in crime at the prison, Warden Ishihara. Ishihara is a corrupt prison warden who delights in exercising sadistic authority over the prisoners by regularly conducting beatings or giving out [[DisproportionateRetribution punishments that are massively out of proportion to minor offenses]]. Ishihara gives prisoners to Sasaki to rape and proposes murdering those who discover the truth to cover his tracks. When the series' initial hero, Sakuragi, finally defeats Ishihara, he gives the warden the evidence of Sasaki's crimes to make Ishihara leave his friends alone. Ishihara's response is to stab him.
* CrowningMusicOfAwesome: The opening definitely qualifies. Heck, it's even sung in SurprisinglyGoodEnglish.
** The ending too.
* FridgeLogic: How did Yokoyama know Mario wanted to be a boxer and thus [[spoiler:smash his hand]]? Mario had barely even begun to consider boxing as a future career/dream, it wouldn't exactly be common knowledge.
* MoralEventHorizon: Sasaki's [[spoiler:raping of inmates]] has pretty much put him across the line.
** Ishihara [[spoiler:throwing away the key to 2-6 during the fire evacuation]], only topped by his later action of [[spoiler:killing Kumagai]]. Even Ishihara himself seems disturbed by the latter.
* TearJerker: It's classified as drama. Better bring tons of tissue paper with you to wipe off your tears.
* TheWoobie: All of the main prisoners. Seriously.
** IronWoobie: And yet, they take it all in stride.