One possible scenario could be that Allen is forced into a situation where he has no other choice but to become a Noah. Maybe he is tricked by a powerful Noah who manipulates his past traumas and the power of Innocence within him. The dark side of the Noah's power might seem appealing in some way, like offering him a way to end his constant struggle against the Akuma and the Earl.
One key plot element could be the internal struggle of the D Gray - Man character as they start to understand the Noah's perspective. Maybe they see some similarities in their fight against a common enemy that they didn't notice before. Another element could be the relationships that form. The D Gray - Man character might start to form alliances or at least truces with some of the Noahs, which would be a huge shift in the story's dynamics. Also, the exploration of the Noah's powers and how they can be used in different ways could be a significant part of the fanfic.
The character development would be drastically different. Instead of growing in the ways of the D Gray - Man, they would now be influenced by Noah values. They might become more ruthless as the Noah are often depicted as having a more cut - throat approach. Their view of the world would change from seeing the Noah as the enemy to seeing their former allies as the opposition. Their relationships would also change, becoming more complex as they try to navigate their new identity among both Noah and former D Gray - Man comrades.
The story could explore the origin of the Noah and how Allen's connection to them is deeper than anyone thought. Maybe his family has some hidden ties to the Noah. This discovery could be the catalyst for his transformation. As he becomes a Noah, he might start to uncover secrets about the war between the Exorcists and the Noah that were previously unknown. This could lead to a re - evaluation of the entire conflict in the D Gray - Man universe.
One great D Gray - Man Noah Family fanfic is 'The Noah's Redemption'. It offers a unique take on the Noah family members, exploring their backstories more in - depth. It gives a different perspective on their actions and motives within the D Gray - Man universe.
Many D Gray - Man Noah Lavi fanfics also touch on the theme of sacrifice. Given the dangerous nature of the world in D Gray - Man, Lavi may be put in situations where he has to sacrifice something - it could be his own safety, his relationships, or even parts of his identity. Writers like to explore how he copes with these difficult choices and what the consequences are for him and those around him.
One common theme is his struggle with his identity. Since he has this complex connection to the Noah, many fanfics explore how he deals with that part of himself.
Another approach is to have a story where the abused child has a connection to the D Gray - Man Noah world without realizing it at first. For example, the child could be a descendant of someone important in the D Gray - Man lore. The Noah, sensing this connection, try to use the child for their own purposes, but as they interact more, they start to feel empathy for the child's situation and have a change of heart. This would explore themes of redemption and the power of human - Noah relationships.
One common theme is the origin of the Noah and their connection to the Mother. Many fanfictions explore how the Noah came to be and what role the Mother played in their creation. Another theme is power. The Noah Mother is often depicted as a very powerful entity, and fanfictions may explore how this power is passed down to the Noah or how it affects the world around them.
First, you need to research the D Gray - Man Noah universe thoroughly. Know the characteristics, powers, and motives of the Noah characters. Then, when creating the abused child character, give them a believable backstory and personality. For the plot, think about how the two elements will interact. Will the Noah be the savior of the child? Or will there be a more complex relationship? You can start with a simple outline, like the introduction of the child's situation, the encounter with the Noah, and how their relationship develops over time.