'baki oc fanfiction' basically is fan - created stories centered around original characters in the Baki world. Some might be action - packed, with the OC showing off their fighting skills against Baki's foes. Others could be more about the emotional side, like the OC forming a deep friendship or a romantic relationship with a character from the original Baki story.
Baki Hanma is the central figure in the 'baki light novel'. But there are also other important characters like his opponents. For example, some of the strong fighters he goes up against play significant roles as they test Baki's skills and help in his growth as a martial artist. There may also be characters who are related to Baki in some way, like his family members or his trainers, who influence his journey in the martial arts world.
The key characters in the ending story are Baki Hanma and his father Yujiro Hanma. Baki is the protagonist who has been on a journey of self - improvement and becoming a stronger fighter. Yujiro is a very powerful and intimidating figure who Baki has to face in the end.