Esumaru(Ace the Bathound)-On a particularly dark and eerie night, Catwoman engages in her usual criminal activity in order to get Batman's attention. Naturally, she succeeds in her endeavor, and a chase ensues. She attempts to shake him by cutting through the Goth-Ahm pet cemetary, and eventually does after knocking over one of the headstones, causing Batman to trip and lose Catwoman. Slightly aggravated by this, Batman quickly departs. But unbeknownst to anyone a spirit of some kind emerges from the destroyed headstone. The next day, news was spread throughout Goth-Ahm about a large dog terrorizing random people. Thinking there must be more to the story than that, Batman soon investigates. After hours of searching for the supposed dog, he spots the royal guard pursuing a strange looking animal on the street below, and then follows, thinking it could be the dog. His guess turns out to be right, as the animal is soon cornered. The guardsmen move in, prepared to kill it if necessary, but before they get close enough, the dog seems to notice Batman on a nearby rooftop. It's eyes glow a ghostly white, and suddenly both Batman and the dog are transported to an abandoned building several streets over. Batman wonders what just happened...and to his surprise, the dog answers his question! He states that his name is Esumaru, an ancient servant of the Watanabe family, who swore loyalty even in death. He then explains that the headstone in the cemetary was his, and by removing it from his grave, his spirit was released. Upon being released, he began to seek out any living member of the Watanabe family. Because of his super-accute sense of smell, Esumaru was immediately able to determine that Batman was a Watanabe. He then vows to serve Batman in any way he can, which Batman trie to politely refuse, but to no avail.
Prank: Warui Yumoa-A teenage orphan boy who would constantly play practical jokes on the people of Goth-Ahm. And while his pranks were very elaborate and somewhat creative, he couldn't help but leave a very obvious calling card every time, and was constantly caught and punished by the royal guard. One night, while wandering the streets, he heard someone calling his name. Unfortunately, that someone was none other than the Joker! Paralyzed with fear, Warui could only stand there, still as a statue, as Joker stated that they had something in common. As stated by Joker, they were both "misunderstood" and "unappreciated" for the work they do. It was then that an idea formed in Joker's twisted mind. He offered to take the boy in as his apprentice, which Warui accepted in both excitement, and in fear of what Joker would do to him if he refused. After donning what Joker referred as the "appropriate attire" Warui was then christened Joker's "offical" apprentice, and given the name Prank.
Zebra-Man Brothers: Shiro & Kuro Shimauma-If you need to hire a professional ninjas to carry out a dangerous task...then these are the last people you want to consider. Twins Shiro and Kuro Shimauma, also known as the Zebra-Man Brothers, might seem intimidating, but they're usually so busy arguing with each other that they completely forget about the task at hand. But that doesn't mean that they're completely incompitant, because when they do focus, they can be quite deadly. Both brothers' bodies are decorated with zebra-pattern tattoos(Shiro's body is white with black zebra stripes, while Kuro's is black with white stripes), and by channeling energy through their tattoos, they are able to create a dizzying vertigo effect. Also, when in close proximity of each other, the brothers can create enough energy to use a special magnetic technique, which attracts and repels anything accept metal.
Notes:
-The reports of Esumaru "terrorizing" the people of Goth-Ahm were greatly exaggerated. He simply examined them to determine wether or not they were members of the Watanabe family, but otherwise left them alone.
-Not only can Esumaru's sense of smell discern one person from another, it can also track the scent of demons and other supernatural beings.
-While Esumaru prefers to be addressed as Batman's partner, most people(including Goth-Ahm's criminals) often refer to him as Batman's pet, much to Esumaru's displeasure.
-Harley Quinn treats Prank more like an adopted son than an apprentice. Joker, on the other hand, gets bored of the boy mere days after taking him in, and contemplates killing him just for the fun of it.
-The Zebra-Man Brothers are not immune to the vertigo effect of their tattoos, and this weakness is often exploited to defeat them.