The female demon could save Doomguy's life in a crucial moment. This act of kindness makes Doomguy question his views on all demons. He then starts to show her small acts of kindness in return, like sharing his limited supplies. As time passes, they realize that they have more in common than they thought. They both might be fighting against a greater evil that controls the demons in a way that the female demon doesn't like either.
It can start with mutual distrust. Doomguy is used to killing demons, and the female demon is afraid of him. But when they are forced into a situation where they have to rely on each other to survive, like being trapped in a small area surrounded by more powerful demons, they start to see each other in a new light. They begin to communicate, first out of necessity, and then gradually become more open with each other.
Another way is through shared goals. If there is a powerful demon lord that both Doomguy and the female demon want to take down for different reasons. Doomguy wants to save humanity, and the female demon might want to free herself from the tyrannical rule of this demon lord. Working together towards this goal, they get to know each other better. They might have arguments along the way about the best methods to use, but through these interactions, their relationship deepens.
A possible plot is that the female demon is a half - demon, half - something else (like an angel perhaps). Doomguy is intrigued by her dual nature. As they team up, she tries to resist her demonic instincts while Doomguy tries to trust her. Their relationship could be full of tension as they both struggle with their own natures and the outside forces that want to keep them apart.
Their relationship could develop through shared battles. When they fight side by side against common enemies, they start to trust each other. For instance, in a fight against a group of dark mages, Natsu and the female demon realize that they complement each other's fighting styles. Natsu's brute force combined with the female demon's more strategic and stealthy attacks make them a powerful duo.
Well, in female Doomguy fanfiction, often the character design is really cool. She can be depicted as having a more sleek and agile look compared to the bulky male Doomguy. This can affect how she moves through the levels and battles enemies. Also, the relationships she forms, whether it's with other survivors or even some reformed demons, add depth to the stories.
You can start by looking on fanfiction websites like Archive of Our Own (AO3). It has a large collection of fan - created works, including female Doomguy fanfiction. Just search for 'female Doomguy' in the search bar, and you'll get a list of relevant stories.
The relationship can be developed through shared experiences. For example, if they face a common enemy together. Yusuke's demon powers can be used to protect Keiko, which deepens their bond. Also, communication is key. Yusuke can open up to Keiko about his new life as a demon, and she can share her fears and concerns about his transformation.
In fanfiction, the relationship might start with curiosity. Kushina could be curious about Naruto's demon side. She starts to study it and in the process, gets closer to Naruto. As she helps him understand and control his powers better, they become friends. Then, as they spend more time together, they realize they have feelings for each other that go beyond friendship. They support each other through difficult times, like when Naruto has to face the negative aspects of his demonic form, and Kushina has problems in the village. This continuous support deepens their relationship.
At first, there might be a misunderstanding between them. The fem demon foxes might mistake Naruto for someone who wants to harm them. But Naruto, through his actions of kindness and protection, clears up the misunderstanding. This makes the fem demon foxes feel guilty for misjudging him and they start to make amends, which is the start of a beautiful relationship.
A prevalent theme is the oc bringing a different perspective to the Doom world. Since the Doom universe is so dark and violent, the oc can be a source of light or hope. For example, the oc might have special powers or knowledge that helps Doomguy in unexpected ways. Also, the theme of redemption can be present if the oc has a troubled past and Doomguy's actions inspire them to become a better person. In some fanfictions, they might also face challenges together that test their relationship, like dealing with a powerful new demon threat or a moral dilemma within the Doom setting.
Writers often start with a conflict. Maybe the female demon attacks Naruto or his friends at first. Then Naruto shows her kindness or spares her life, which makes her curious about him. For example, Naruto might see that she's not truly evil but is acting out of desperation. From there, they start to have small interactions that gradually build trust. They could share their life stories during these interactions, which deepens their connection.
There's a fanfic called 'Doomguy in the Hidden Leaf'. In this one, Doomguy gets transported to the Naruto universe. It's interesting to see how he interacts with the different ninja clans, especially when his no - nonsense attitude clashes with the more traditional ways of the Leaf Village. It's a short but engaging read.