as you can tell from from the tittle ,it's a boss from the game called dark souls, but if you are a dark souls fan ,you'll know there's no such boss in that area,but the thing is that's an oc characters so it make sense in that situation;it's not a long story just a oneshot,if you can sday that,i just drew the creatures and mimiked wiki style on what his attack are and how he fights. but there's some story and lore describing brief histiry of that boss