In a secret laboratory, an unknown man created human-dog hybrids. The first one worthy of keeping alive was Bornes. A bit stocky, he was raised in seclusion. His vocal chords were not fully developed and he could not speak human language. He did have intelligence, however, and over time was able to communicate using American Sign Language.
Bornes was the subject of many experiments, and as such became a very angry, untrusting person.
After much study, the second iteration was created: Bornes B., or simply B for short. Being raised more like a child rather than an experiment, B developed a loving and trusted attitude more in line with his tamed canine heritage. Able to speak English, he is much more reminiscent of a human than the first Bornes ever was.
Eventually, Bornes escaped the facility and kidnapped B. They lived together, where Bornes attempted to mentor B. B is able to read and sign ASL, but his preferred communication is still spoken English. Since Bornes is not deaf, the conversations between the two of them are often littered with B's frequent code-switching.
Bornes does not trust humans and has developed a mild case of agoraphobia due to this. He believes he is alone in the world and tries to convince B that all people are evil and will treat them terribly. B, having not experienced the same troubles past as his older "brother," does not feel the same way and there is much contention between the two.
Eventually B leaves Bornes and tries to live his own life. But as he is ignorant to many things, he frequently becomes the brunt of many jokes when unable to complete simple, common-sense tasks (such as cooking, laundry, or dog-oriented mannerisms like barking or howling).
B is on a journey to find more "people" like him and experience the world as humans do. Bornes, on the other hand, hates the world and would like nothing more than to see it burn.