This is a roleplay build for Longbow Oolan, based on the information gathered from item descriptions and the black phantom encountered in 1-4. I will go over the build and link my sources below.
Stats:
The stats and equipment are based on the black phantom encountered in 1-4. [1]
The source used had several stats that were incompatible with both the health of the phantom and starting class stats. I decided to use the Vitality stat of the phantom rather than it's HP. In order to get this I chose the knight class. If you want to change it to hunter, for better starting gear, it is recommended you shoot for a similar health total.
In addition the use of firestorm and the silver catalyst is responsible for the Intelligence.
Equipment:
You will be using the White Bow as your main weapon, with the Kiliji if the enemies get too close. Both of these items can be aquired in World 4. In addition, you will need White Arrows. White arrows are very limited and in the begining you will need to trade items to Sparkly in 1-4.[2] You can only find a total of 128 white arrows from Sparkly, with the bow, and Patches. Contrary to popular belief, you can get more, but it is hard.
Above Sparkly's nest, there are hawks. Shoot them with light arrows and they will have a chance to drop 5-10 white arrows.[3] I recommend using the Searching Greatsword and the ring of avarice to increase the drop rate.
Sources:
[1] http://demonssouls.wikidot.com/bp-white-bow
[2] http://demonssouls.wikidot.com/crow
[3] http://demonssouls.wikidot.com/white-arrow