Now for Blurr's baclstory, one in which I think is going to explain so much about him and his character.
Blurr grew up as an only child, his creators being two Femmes who were indeed very loving to him. His life was good, although he did suffer a lot in school and had hard times with learning, which his creators blamed on spending too much time being free (which is why they 'killed' his Cyberdog: Erotinas)
His creators enjoyed the additcing stuff, but it was always rare seeing them with high grade since it was never their favourites. In the long run, he still remembers when his creators urged him to have some, which soon brpught him into the addiction.
Whenever he had it, his mind could function. He would do better in his working lessons and classes, and he found it much easier to understand everything, unlike withput it, he would be lost. He doesn't know how many times he would take it, but, he only saw it for exactly what he should be because no one liked him like how he was.
He couldn't break from it, he tried multiple times. Whenever he did, he found that he would basically be stupud and be immediately disliked by others, which would bring him back to it once again. His creators ended up then dying in a freak accident, and it didn't take long for Blurr to run away from the orphanage he was placed in.
Even when he did get money, it was quick to be spent on his addiction. It got to a point of lowness, literally dying out on the empty streets, that is how it was for several days until Salvage found him and helped him recover.
Blurr knew that Salvage's creators didn't like him for who he was, but Salvage didn't mind that he was this stupid self. If it got bad being away from it for so long led him to break out in fits, which is what caused tension multiple times. He felt useless many times too, which sometimes made it worse.
The ship they were both on when the bots first found them just so happened to be the one they had stolen (Blurr's idea) when their town got attacked due to the building war that corrupted society. That led them all the way to Earth, save the cave people and go straight into an eternal slumber until they were both awoken by Sigma 17.