Hey Nesy. Longtime dungeon master here, one that has had experience dungeon mastering 1 x 1. It's a lot harder to do without a second player but I think I am up for the challenge. I've wanted to actually use one of the many worlds I have built only to be told people want to stick to faerun (Dungeons and dragons) or the world of darkness (Vampire the masquerade). If you're still looking for a dungeon master's please dm me! I would gladly accept any friends of yours too! We'd likely either play first addition, a custom system of my own, or a simple system like Lazers and feelings or Dungeon World.

Here are some settings I have that match up with your interest:

Forenia: A magical world suffering a plague that only the clergy can cure. The population is low, people suffer diseases, curses and magic is wild and erratic. Adventurer's are the seldom few who dare travel between the large cities, risking life and limb for the freedom, isolation, and secrets that lie just outside the gates.
-Magic
-Ancient
-Low fantasy
-Dieties/witchcraft
-horror
-adventure
-Mythology
-DnD
-Dark themes

Sabrin: A world where ancient technology and magic are the most dangerous weapons and most intuitive advances. Ancient stargates have been uncovered and agents of various factions on the world send adventurer's to chart new worlds and try to uncover the mysteries of the 'ancient ones'. 
-Dnd
-high fantasy
-Science fantasy
-Politics
-Adventure
-Action

I can try to include romance but don't expect me to perform a miracle.