Indeed, Wolverine and Sabertooth are considered brothers in the comics. However, their interactions are filled with rivalry and hostility, making their brotherhood a very strained one.
A common theme is their rivalry. It's often explored in depth, like in 'The Eternal Rivalry' fanfic where their battles are not just physical but also a battle of wills. They constantly try to outdo each other.
One great Sabertooth vs Wolverine fanfiction is 'Clash of the Mutant Titans' on FanFiction.net. It really delves into their complex relationship, exploring their past battles and grudges. The author does a wonderful job of writing their intense fight scenes and the underlying emotions that fuel their rivalry.
One popular Sabertooth OC fanfiction could be about a new member joining the Sabertooth guild. This new character might have a unique magic ability that helps the guild in a big way during a major battle against a powerful dark guild. They could bring in new strategies and also form interesting relationships with the existing members like Sting and Rogue.
One common theme is acceptance. The oc usually has to find a way to be accepted into the sabertooth guild, which can be a tough group to break into. Another theme is growth. The oc often starts out as a bit of an underdog and grows in power and confidence as the story progresses.
They could also be allies in some stories. If the OC has a similar view on the world as Sabertooth, perhaps a more survival - of - the - fittest mentality, they might team up. This could lead to some interesting plot developments as they face off against other mutants or even humans who oppose them.
One common theme is redemption. Often the OC has a troubled past and Wolverine helps them find a new path. For example, in many stories, the OC might have been used as a weapon and Wolverine guides them towards a more positive life.