One idea could be to create an original character (OC) who has a unique power that catches the attention of a goddess. For example, an OC with the ability to manipulate time on a small scale. The story could revolve around how this power affects the relationship between the OC and the goddess, and how they team up to face challenges in the danmachi world. Maybe they have to deal with a powerful monster that is immune to normal attacks, but the OC's time - manipulation power gives them an edge in battle.
For character development in a 'danmachi oc cum goddess fanfic', think about the character's arc. The OC might start as a novice adventurer with little confidence but gradually gain more self - assurance as they gain experience and the support of the goddess. Consider their moral compass too. Do they have a strict code of ethics, or are they more of a morally gray character? This will affect their decisions in the story. As for the goddess, explore her backstory in relation to the other gods and goddesses in the danmachi universe. Maybe she has a rivalry with another goddess, and this affects how she treats the OC. By understanding these elements, you can develop complex and engaging characters for your fanfic.
One of the great Danmachi fanfics is 'A Different Perspective'. It offers a fresh take on the characters and their relationships within the Danmachi universe. The story delves deeper into the backstories of some minor characters and makes them more significant. Another good one is 'The Unseen Adventures'. It takes the characters on new quests that are not in the original story, adding more excitement and mystery.
The Danmachi light novel is finished. The author completed the series, providing a satisfying conclusion to the adventures and developments of the characters.