You're going to need a guide to understanding the lore and atmosphere. The hard mode is not contained to the game play. Bloodborne, for example, has the atmosphere change based on certain unlocked events and paths you choose to go down. Even if you notice the change in atmosphere, you're not going to understand how it fits together with the story.

I'd just watch a YouTube walkthrough if you don't want to play. Playing the game, alone, is not enough to fully appreciate any of the Souls games.