Honestly, 'y f n' in fanfic could be a random combination of letters without a widely recognized meaning. Maybe it's a made-up term by the author for a special plot element or character trait.
One day, Y N was on a plane, feeling both excited and a bit nervous for the journey ahead. As Y N was settling into the seat, suddenly, the members of BTS gang walked by. Their presence was electrifying. Y N couldn't believe their eyes. Jin flashed his warm smile, while J - Hope's positive energy seemed to fill the whole aisle. Jungkook was looking cool as always. Y N shyly said hello, and they were kind enough to start a conversation. It was like a dream come true for Y N on that plane ride.
One common theme is probably the healing process. Since there's the 'hurt y n' part, often the BTS members will be involved in helping the character heal from whatever has hurt them.
I'm not entirely sure specifically what that particular 'bts y n is a hybrid hurt fanfiction' is about without more context. It could be a fan - created story that involves the BTS members, some kind of 'y n' (which might be a made - up or specific character in the fanfic world), and it's a 'hybrid' concept which could mean a mix of different elements like human and something else, perhaps supernatural, and 'hurt' might imply there are elements of pain or emotional distress in the story.
One common theme is friendship. Since it involves y n meeting members of two big groups, the stories often focus on how new friendships are formed. For example, y n might bond with a member over a shared love of music.
Well, perhaps Y N is trying to get closer to the stage to see BTS better. They accidentally trip over some equipment that was not properly secured near the front of the stage area. Y N falls and bruises their knee and elbow. They are really sad because they don't want to miss any part of the concert, but they also know they need to take care of themselves. Other fans around them start to create a bit of space and offer tissues and water while waiting for the medical staff.
Y N could be on the plane for a very personal reason, like going to visit a sick relative. The BTS gang, on the other hand, is on a promotional tour. Y N is initially hesitant to approach them. But then one of the BTS members, say RM, notices Y N's distress and starts a conversation. They end up sharing their stories. The other members join in. During the flight, they play some games together, like a simple guessing game. By the time the plane lands, Y N has made some great friends in the BTS gang and has a new outlook on life.