A fanfic could explore a what - if scenario where Ryuga doesn't turn to the dark side. Maybe he and Gingka become friends from the start and they train together, sharing their beyblade techniques. This would change the whole dynamic of the story and lead to them competing in a more friendly way in tournaments.
One possible beyblade ryuga love story could be that Ryuga meets a girl at a beyblade tournament. She is initially intimidated by his intense presence but is also drawn to his skill. Ryuga, who is usually focused only on winning, starts to notice her constant presence and support. As time passes, he begins to soften towards her, and they develop a connection that grows into love over the course of their beyblade adventures together.
The OC could be a healer in the blading world. Ryuga gets seriously injured during a battle. The OC takes care of him and during his recovery, they start to bond. Ryuga, who is usually so tough and independent, finds himself relying on the OC. This newfound closeness makes him question his own feelings. They could then go on a journey together to find a rare blading item, with their relationship evolving along the way.
One potential match could be a fellow dark - side blader who has a change of heart. They would understand Ryuga's past and the struggles he has faced in the world of Beyblade. Together, they could try to break free from the darker aspects of their lives. Or perhaps a mysterious newcomer to the Beyblade world. This character could bring a fresh perspective to Ryuga's life. She could be intrigued by Ryuga's power and presence, and Ryuga, in turn, would be curious about her different way of looking at things. Their relationship could be based on mutual discovery and attraction.
One possible scenario in this fanfiction could be that Gingka and Madoka start off as friends, gradually realizing their deeper feelings for each other during their beyblade adventures. For example, after a tough battle where Gingka is injured, Madoka takes care of him and they share a tender moment that makes them both aware of their love.
One possible fanfiction could be about Gingka and Madoka going on an adventure together to find a rare and powerful beyblade part. Along the way, they face various challenges and have to rely on each other's skills. Gingka uses his beyblade battling expertise, while Madoka uses her technical knowledge to repair their beys when needed.
It could be Doji. He's always been after powerful beyblades and Gingka's Pegasus is one of the strongest. He might kidnap Gingka to get Pegasus and use its power for his own dark plans. Another option is Ryuga. Although he has his own code, in some fanfictions he could be desperate enough to kidnap Gingka to prove his dominance in the beyblade world. Also, a new and unknown blader who is jealous of Gingka's skills and popularity could be the antagonist and kidnap him to make a name for himself.
One plot idea could be that Gingka is kidnapped by a rival blader who wants to steal his special beyblade techniques. The rival could hold Gingka in an abandoned warehouse and try to force him to reveal his secrets. Another idea is that a group of evil bladers kidnap Gingka to prevent him from competing in an important tournament. His friends then have to search for him and rescue him before the tournament starts. A third plot could be that Gingka is kidnapped by a mysterious figure who believes Gingka has a hidden power within him and wants to harness it for their own evil purposes.
In some fanfictions, Gingka and Madoka might time - travel back to the origins of beyblades. They learn about the history and secrets of beyblades together. This could involve meeting the very first bladers and getting involved in ancient beyblade battles that shape the future of the sport they love so much.
I'm not sure about the 'best' but there are many talented authors. Some authors who have a deep understanding of the characters and write engaging stories are often popular. You can check on fanfiction platforms like FanFiction.net or Archive of Our Own to find authors with high ratings for their Gingka and Madoka fanfictions.