- The anime is known for having Bishie Sparkles literally all over the place, and it even seems gratuitous at times. However, it starts to make sense in Episode 9, when Jyugo states that after he met his friends in Cell 13, his gray world started to shine in bright colors. All the sparkling colors represent Jyugo's view of the world when he's with his friends, and to further the point, the scene where he's depressed and isolated after the New Year's incident is shrouded in monochrome.
- Further going on that, if we're seeing the series from the point of the (male) inmates, then...the fact that almost all female characters have big breasts makes sense.
- The show having a Cast Full of Pretty Boys makes sense, as this is a prison story, so the only people around would be good-looking men (only one woman is in the major cast, and she's a prison officer), with a few looking and acting effeminate.
- Jyugo pulling blades from his arms is a play on the prison trope of carrying around hidden blades (shivs and shanks)
- Everybody in Nanba Prison, prisoners and guards, has a number in their name.
- "Elf" is German for "11". He was a former Nanba prisoner.
- Jyugo's dad is known only as Inmate 610. The best guess for his name is Shito, as in "shi"-"to" (6-10).
Fridge / Nanbaka