After coming up with the title Gastown, the first characters who popped up out of the ether were Juan Grimm and his twin brother, Carlos. There was no real thought about choosing the names, they just appeared and immediately started taking on personalities of their own. Like all things Gastown, there is a heavy influence from the writings of Charles Dickens. They are waifs, cast adrift in the roughest section of the Four Kith, in the slumlands known as the Slough. They survive by any means they can to get by. They know no other way. A chance encounter with JoJo Dickens offers temporary salvation and also a fork in the road for their development.

I needed a physical trait to differentiate the twins, and unfortunately this cost Juan his right eye. The imperfection saved him from the unwanted attentions of Cotter Sullivan, but cast him back on the violent streets and the dangerous trade of pickpocketing. 

Initially, Juan is portrayed as the smarter of the twins. However, this is not strictly true. Juan is just more cautious whilst Carlos is headstrong. Ultimately, both of them are killers. Carlos by deed, and Juan by words.

There are many prototypes influencing the development of the twins: the Biblical Cain and Abel, Castor and Pollux from Greek mythology, and Romulus and Remus from the founding of Rome, and feuding over their own city on the seven hills. However, the strongest sibling connection is with modern day mythology, and Ronnie and Reggie Kray, gangsters from the East End of London. Although not conjoined like Chang and Eng, the original Siamese twins, Juan and Carlos share a deep connection, which is sundered by jealousy, abuse, rage, and ultimately madness.

Juan represents the seedier side of Gastown, and how difficult it is to rise out of the mire if you try to do the right thing and inspire people to challenge armed authority. His way out is to physically leave, though not by his own choice.