Well, it might also indicate that he is just a very punctual person when it comes to consuming the content his friends share. He could have a habit of regularly checking stories as soon as they are available, and since he is your friend, yours is one of the first he sees. However, if this is a consistent pattern only with your story, then the chances of him having a particular interest in you are quite high.
It might also be that he is just a very active social media user and he has his notifications set up in a way that he sees your stories right away. However, the fact that it's always your story that he's first to view does make it seem like there's a special interest there. It could be that he values your friendship a great deal and doesn't want to miss out on any part of your life that you share through your stories.
It's also possible that he is just a very active user of the platform and happens to see your stories first. However, if this is a consistent pattern, it's more likely that he has some kind of personal interest in you, whether it's friendship or something more. He could be someone who values your posts a great deal and wants to be among the first to engage with them.
It could be your best friend. They might be really interested in your life and eager to see every update from you, so they always check your stories first.