I am a huge * souls game fan mostly because I absolutely love the way the game tells stories
In Dark Souls II there is a character named "Manscorpion Tark", his story is very unclear but he makes hints that his master is a great ineffable being of white. Then after completing some tasks that he besets on you he says the following
"What skill. You've defeated my master.
But our master never dies, only changes form, so that he may seethe for all eternity.
Brave human, you have yet to face your greatest perils.
Take these. May joy await you at the end of your travels."
Which is obviously referring to seath the scaleless from DS1, In fact many of the lord souls that you get from the game are in reference or have their origins to Dark Souls 1
There are a lot of things that you kind of have to 'go out of your way' to find but it is really rewarding for the people who love the lore of the game