a) something good
b) something bad
c) an insult
d) sentence filler (basically saying it just to say it)
b) "my stock portfolio is doggin' it big time"
c) "I hear Pauls been doggin it' like a fairy"
d) Sean: "look all i'm saying is that sex is always better when you pay for it!"
Paul: "doggin' it with the prostitutes, atta sean"