Luis is a prince and Gil is his manservant & bodyguard. They have a pretty fraught relationship, because Luis is the next king of his country, an empire which invaded Gil's country. Gil was enslaved for years as a gladiator, and was given (begrudgingly lol) to Luis as a gift when he became crown prince. They have a purely professional master-servant relationship except for when Luis gets drunk and they end up sleeping together. Luis usually loses his memory after getting drunk so he never remembers any details. Their relationship develops past that in the manga! I hope you can get around to reading it! 💕