I’ve got you!! It’s on an app called Kakaopage, where the official Korean uploads are, which you can make an account and read one episode per 12 hours (with the ticket system thing) and also a telegram group translates it called https://t.me/s/selenachaan ! You should probably not make a telegram account though due to it being popular for bad deals and crimes in it. Use the website and google translate features on whatever app you’re using. Happy reading I hope you enjoy it as much as I do!! also, make sure to look up the Spanish names and Russian ones as that is majority of the fandom ATM😼😼❤️❤️
In season four, he tells selena that to make up for hiding her identity she should stay by his side forever (marriage) and then they get married. 
Celestine and Simon are granted the title of Duke I think? Some high society role, and Celestine marries rose.
On Selena’s wedding with Ignis, she is found to 

be pregnant with his kid. Adorable! 
Letio ends up with the pink haired mercenary I believe
Rowan is.. being Rowan? I forgot what he does. If you need more, search up the villain discovered my identity spoilers and there should be a whole forum with twenty pages dedicated. I copy and pasted everything I have in my notes to the comment haha :3