Zoopark

Zoopark (ザアパルク, Zā Paruku) is a criminal organization made up of wanted criminals. Its leader, Thumbnail, is known for eponymously pulling out the thumbnail of his victims.

Description
They move their hideout every four days that even international police cannot locate them. In their latest hideout in Yokohama, they have 18 heavily-armed violent criminals and security cameras. Moreover, their main entrance door is highly secure, which is the kind used in bank vaults that cannot yield even to a bomb explosion.

Influence
They are a notorious gang whose status increases the heavier they commit crimes and atrocities. The gang also has connections to various local criminal groups. As such, Thumbnail flaunts that they can summon dozens of newly-recruited criminals with a single phone call.

The Guild Aftermath Arc
After the fall of Moby Dick on Yokohama waters, Zoopark is one of many criminal groups eyeing the Guild's alleged fortune. In an attempt to pressure the Armed Detective Agency into spilling the whereabouts of the Guild's fortune, they ransack Café Uzumaki and tear out its owner's thumbnail. However, the Agency is unthreatened and easily locates their hideout. Thumbnail calls for aid from local criminal groups, only to be rejected after learning that they are up against Yokohama's infamous Armed Detective Agency. In the end, Zoopark is taken out by the gifted detectives.

Later, the gang comes across Louisa May Alcott in the slums and questions her about the location of the Guild's fortune. As she denies knowing about it, Thumbnail threatens her to divulge where her boss is, but she denies him once more. Seeing her uselessness, Thumbnail holds Louisa at gunpoint ready to dispose of her, upon which Fitzgerald punches him with 50¢ worth of power. As Louisa offers all her possessions to Fitzgerald to fuel his ability, the gang gets entirely defeated.