ex is always the first to watch my stories

Well, 'ex' is probably your former partner. Maybe they still have an interest in your life and are eager to see what you're up to, so they are always first to watch your stories.

Ex might be your former partner. Maybe they still have an interest in your life, so they are always quick to check your stories.

It could mean that your ex still has some level of interest in you. Maybe they miss you.

It could mean they still care about you.

Maybe they still have some interest or curiosity about your life.

There could be several reasons. Maybe they miss you and want to know what you're up to. Or it could be that they're comparing their life to yours. Another possibility is that they're just bored and looking for something to do, and your stories happen to catch their attention.

Maybe they still have some interest in your life or just happened to come across your stories by chance.

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.

He might be really into you. He wants to know all about you as soon as possible.

It could be that they haven't fully moved on and are keeping tabs on you. Or perhaps it's just a habit they haven't broken. Maybe they still care about you on some level and this is their way of staying connected, even if it's in a passive way.