well...you cant get a dog lol, it doesnt exist atm in SRO
You can get a grey wolf ingame for 1 million at each stable shop.
You can got a white wolf, a squirel, or a monkey at item mall (
real money)
White and grey wolf are the same, just color difference.They attack mobs with you and grow up. I got a grey wolf and im happy, it make some good damages once it is at the same lvl as you
monkey and squirrel are the same, just select the one you want
I guess they are really usefull as they pick up money/items while you are grinding.
So, if you can, i'd say got for wolf and squirrel or monkey
hope it helped you