A frequent theme is the idea of care and support. When a character has a sunburn in these fanfics, it often leads to other characters showing concern, like bringing them ointment or offering shade. Another theme is the transformation. The sunburn can be seen as a catalyst for change in the characters, whether it's a change in their attitude or their relationships. For instance, in some fanfics, a character who was previously aloof becomes more approachable after experiencing a sunburn and the care from others.
One popular theme is the exploration of the characters' mental states in more depth. Since Omori has such complex characters dealing with psychological issues, fanfics often delve into how they might overcome or further struggle with their inner demons. Another theme is alternative universes. Writers create different scenarios where the events of the game could have taken a different turn, like what if a certain character made a different choice at a crucial moment. Friendship is also a big theme, showing how the characters' relationships could develop in new and interesting ways outside of the main storyline.
One of the main themes in Omori's story is the exploration of the self. Omori is constantly trying to figure out who he is and what his place is in the world. Another important theme is the significance of relationships. His interactions with friends and foes alike shape his understanding of himself and his situation. Also, the theme of facing one's inner demons, which is closely related to mental health, is prevalent throughout the story.
Despair is a very common theme. In these fanfics, the characters often face hopeless situations, much like in the bad ending of the original. Another theme is loss, whether it's the loss of a loved one or the loss of one's own sanity.
I don't have the exact name of the person who created the Omori manga at hand. It could be worth doing a search on manga databases or asking fellow manga enthusiasts for the answer.
Omori is purely fictional. The story and characters were imagined by the creators, not drawn from real-life events. It offers a fantastical and imaginative experience for players.