Todo's appearances in the JJK manga are scattered. It depends on the specific storylines and conflicts. Sometimes he's in the foreground, and other times he makes cameos to add to the overall narrative.
The 'amigo brothers' story is about two best friends who are also boxers. They have to face each other in a boxing match. Despite their friendship, they are both determined to win. In the end, they show great sportsmanship and their friendship remains intact.