A lot of fanfictions focus on the idea of forbidden love. Since they are on the same side in Talon, but their relationship is often complicated by their own personal issues and the nature of their work. Also, there's the theme of power dynamics. Reaper's more aggressive and powerful nature compared to Widowmaker's cold and calculated one can lead to interesting relationship dynamics in the stories.
The theme of secrecy is quite common. Given their roles in Talon, they might have to keep their relationship a secret from others in the organization. This can add a lot of tension and drama to the fanfiction. And sometimes, there's the theme of sacrifice. One character might be willing to sacrifice something for the other, whether it's their position in Talon or their own safety.
The theme of forbidden love also appears frequently. Given their status as villains and the nature of their work in Talon, their relationship might be seen as something that goes against the rules or expectations within the organization. Fanfics may focus on how they navigate this forbidden aspect while still being drawn to each other.
Some popular themes include their complex relationship within the Overwatch universe. Maybe a theme of redemption for their past actions as they come to terms with their feelings for each other. Another could be the struggle between their loyalty to their respective organizations and their growing affection.
A lot of these fanfictions have a theme of protection. Reaper, despite his menacing appearance, protecting the reader from various threats in the Overwatch universe. There's also the theme of discovery, where the reader gets to discover the real person behind Reaper's intimidating facade, and as they do, a relationship begins to form between them. It's often about peeling back the layers of his character.
One common theme is redemption. Many fanfictions explore the idea of Reaper finding a way to atone for his past actions. Another theme is his loyalty or lack thereof. Whether he's truly against Overwatch or has some hidden motives related to his former comrades.
The exploration of Reaper's backstory in the context of RWBY is also common. Since his backstory in Overwatch is quite tragic and mysterious, fanfiction writers might try to adapt it to the RWBY universe. They could explore how his past experiences in Overwatch might influence his actions and decisions in the RWBY world, such as his views on the concept of heroism and villainy which is very different in the two universes.
A frequent theme is the idea of redemption through pain. In these fanfictions, Reaper's hurt might be a catalyst for him to change or re - evaluate his actions. There's also the theme of vulnerability. Reaper is usually depicted as a very powerful and menacing character, so seeing him hurt makes him more human and relatable. And sometimes, there are themes related to the mystery of his powers and how his being hurt might impact or change those powers in some way.
One common theme is the redemption arc. Given Reaper's rather dark and brooding nature, many fanfics explore the idea of Mercy helping him find redemption. For example, she might try to heal not just his physical wounds but also his damaged soul.
You can start by looking on fanfiction websites like Archive of Our Own (AO3). It has a large collection of Overwatch fanfictions, and you can simply search for 'Reaper x Widowmaker' in the search bar. Another option is FanFiction.net, which also has a decent amount of Overwatch related fan stories.
One common theme is redemption. Since Widowmaker has a dark past and is often seen as a villain, many fanfictions focus on her being redeemed through the relationship with the oc. For example, the oc might show her a different way of life or help her remember her humanity.
Another theme is trust. Since Widowmaker has a complex past and is often seen as a dangerous assassin, building trust between her and the reader is a big part of many stories. This could involve situations where they have to rely on each other in a dangerous mission.