A veteran hunter, an old friend of John Winchester (until their violent falling out), and father-figure to Sam and Dean, Bobby Singer is an old man in a profession where people don't live to become old.
When Sam and Dean are saving people and hunting things and they get into a bind or hit a dead end in their research, they call one person: Bobby. And they aren't the only ones. Inside his home, Bobby has various phone lines with different designations contingent on the caller. He acts as the case manager for his coterie of hunters in North America.
An unofficial librarian, Bobby's dilapidated home is filled and scattered with obscure and unorthodox books, maps, encyclopedias of different religions in various languages. He's a researcher, a scholar, mentor, and strategic master, but also gruff.
Fiercely protective of his adopted sons, Bobby once fought off a demon possession which ended up crippling him for several years. Regardless of how much Dean has idolized his father, Bobby has his highest respect.
"Family don't end with blood, boy." - to Sam in episode 5x01
"Well, boo hoo! I am so sorry your feelings are hurt, princess! Are you under the impression that family's supposed to make you feel good, make you an apple pie, maybe? They're supposed to make you miserable! That's why they're family!" - to Dean about Sam in episode 4x22
"To who, Hogwarts?!" - to Dean after he asked if Bobby could research anything on dragons for a case in episode 6x12
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