These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Chief Ekoda is the head of the Tokyo Police Department, who hides a secret fetish: He has a thing for legs. In fact, while a member of Suitengu's Roppongi Club, Ekoda took the chance to satisfy his feitshes by kidnapping women, holding them hostage and then cutting their legs off before preserving them as trophies, molesting and killing the women himself. His first two victims were his own wife and daughter. Later in the series, Ekoda kidnaps Ginza Hibari and tries to do the same to her before she frees herself. Ekoda is set apart by being a completely human monster and his insane excesses make even the hardened Ginza reevaluate everything she had done to this point.
Mizunokuchi is a sadistic dentist who, as a Euphoric, is granted a multitude of spider-like limbs that he can turn into drills. In the past, Mizunokuchi operated on heroine Kagura when she was due for dental surgery, removing her lower molars while she was still conscious so he could feel her pain. In the present, the dentist takes pleasure in outright tying patients down and simply torturing them to death by drilling through their mouths. He even takes disturbing trophies of the teeth that he carves and polishes afterwards.
Ran Yurigaoka is an esthetician with a thing for tattoos and body art. With his Euphoric powers, he can make his tattoos come to life. Yurigaoka uses them to control other people, playing them as People Puppets for his amusement. His real joy, though, is the Giant Spider tattoo on his back. Yurigaoka uses his fame to find women and uses his powers to give them pleasure, before he paralyzes them by merging the spider with their skin. After this, he has it kill them while they're alive and conscious, but paralyzed the entire time.
Kamiya is a Corrupt Politician who becomes Japan's Prime Minister and schemes to take possession of the Roppongi Club, which caters to every fetish and predilection of the upper classes, away from Big BadAnti-Villain Suitengu, while also gaining control of Kagura for his own purposes. A glutton whose power is to devour anything, before he even achieved these powers, he once drove a couple to suicide over a huge debt, and then took their children to compensate. The son he sold as a child soldier who would one day become Suitengu. The girl, who was only five, he sold as a Sex Slave to be abused and debauched until she was an Empty Shell years later, knowing only how to please men and request money for it.
Crazy Awesome: Seriously, some of the ways Saiga comes up with to wreak havoc with a camera are truly mindboggling.
Add both of Saiga's rescue missions to that, particularly the wedding crasher.
Crowning Moment of Funny: "Yes, I'll be needing you to get me another car immediately... preferably one that can't be BLOWN UP BY A FUCKING CAMERA!"
Niharii's reaction to the diamond lady Euphoric biting off a woman's finger so she could eat a diamond ring is pretty funny too.
"Lady, that's fucked up!"
The entirety of Episode 16, which is a clip episode. It's handled in such a way that it can't be presented as anything but a clip episode as well as adding a new dimension to the series as a whole: It's about the Roppongi Club's accountant tallying up all of the membership fees, then the expenses Saiga has done up to that point, which turns out to be relatively equal. We see various clips and are then shown how much it cost.
In-universe, the screeching of dentist drills — Niharii is shown cowering in an office with his hands over his ears to block out the sound. Of course, the fact the drills were being used by a Depraved Dentist to basically rip a woman's mouth apart probably played a factor in that.
Ho Yay: Besides Bob, Tsujido is really attached to Suitengu. Played with more subtlety than in many anime, though.