Modders never fail to disappoint, and one by the name of Abject had modded Dark Souls to include Guts, the warrior from the manga series Berserk, complete with large sword and matching outfit.'
If this sounds up your street, you can watch a trailer here, and find out more about how to download the mod here, including 3D models and textures, among other things.
Is this the best mod to come to Dark Souls?