I was watching a walk-through of the game and noticed that the player I was watching was somehow getting more souls for each kill. Anyone know how I could do this?
I can think of three possibilities:
You are not playing on the same patch version as them. As time has gone on, the amount of souls dropped has changed. (mostly increased if I am remembering correctly)
They are playing on NG+ or on a higher player through than you. Each time you beat the game, the enemies in the next play through drop more souls.
They are wearing the covetous silver serpent ring or symbol of avarice. Each of these items increases the number of souls absorbed.
I did some hunting based on your comments, and think it is most likely the first option (you are playing on an unpatched version).
listed under the 1.05 patch:
Overall increase in souls gained (~2-2.5 times more)