The Ratman is sort of a species identifier. Anything that lives in dark, dank places and has rodent-like features is a Ratman.
A particularly notable version of the creature comes from Essex, where legend says its the ghost of a homeless man who was beaten to death and then eaten by rats.
However, as stated before, the Ratman doesn't have a single origin. In a way, it's like Bigfoot, which has so many sightings across the world it might as well be a species.
In fact, as a personal anecdote, I live nearby one spot related to a sighting, and it's quite a story.
The Ratman of Cambridge is a cryptid seen in Cambridge, Massachusets. The story goes that a local gang disposed of a body in a sewer system. However, due to the conditions of the sewer, the body managed to reanimate.
Since the now reanimated body had no knowledge of its previous life, it fell in with the rats that inhabited the local sewer.
The thing is, I think I've seen this specific instance of the Ratman. Or at least something I can't explain in the same area. I've already talked about it on the blog section of the website, but I'll retell it here.
I was walking home from a club event- this was back in my Freshman year- when I had to take a detour due to work being done in the road. I had to walk under a bridge, where I heard a strange skittering noise. I thought it might be a raccoon or something, since those are common in the area, so I took a quick peek.
All I heard was a shriek and all I saw was a blinding blue light. I fell back, staring up at what I can only assume was the Ratman as he towered over me. I quickly pulled out my phone, snapping a blurry picture. It let out another deafening shriek before running away.
I'll be honest, the image is sort of a piece of shit, but at least I have evidence of what happened to me in some formmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm.