Perhaps they get left back because of some external factors. Say, an enemy attacked their guild right before an important exam. Lisanna and Natsu were so busy fighting off the enemy and protecting their guildmates that they missed out on crucial study time. They might have also gotten injured during the battle, which further hindered their performance in the assessment, causing them to be held back.
In this kind of fanfiction, they might face various challenges. Maybe they'll have to find their way back on their own. They could encounter dangerous magical creatures and have to rely on their own skills and the bond between them to survive.
A plot could be that Natsu and Lisanna have been longing for a baby. They go through a magical ritual in their guild to increase their chances of having a child. Once Lisanna becomes pregnant, the whole guild gets involved. Everyone is excited and offers their help. Natsu becomes super protective of Lisanna and the unborn baby. There could be a sub - plot where an enemy tries to target Lisanna because of the powerful baby she is carrying, and Natsu has to fight to keep them safe.
Lisanna might face a lot of backlash from the guild. Her friends could be disappointed in her and might not trust her as much. She could lose her standing in the guild and have to work hard to regain people's respect.
One popular storyline is where Natsu and Lisanna go on an adventure together to find a long - lost magical artifact. This adventure tests their relationship and their individual strengths. Another is a story where they have to team up to save the Fairy Tail guild from a powerful enemy. It often involves them using their unique magic skills in creative ways.
One possible plot could be that they discover the pregnancy and start preparing for the new arrival. They might face challenges like how to balance their duties in the guild with the upcoming parenthood. Natsu could be overly excited but also a bit clueless at first.
In this fanfiction, perhaps Amy is in a difficult situation when she gets pregnant. For example, she could be in the middle of pursuing a big career opportunity. The story might revolve around her decision - whether to keep the baby and put her career on hold or to choose her career over the pregnancy. There would be a lot of internal struggle and emotional turmoil.
One possible storyline could be that Naruto discovers he has long - lost relatives. Maybe his father had a secret sibling and Naruto stumbles upon this family during a mission in a far - off village. This new family could be very different from the friends he grew up with in Konoha, introducing him to new ways of life and ninja techniques.
Another storyline might involve Deku having to face some sort of villain threat right before the wedding. He has to balance protecting his loved ones and ensuring the wedding goes on as planned. Maybe a new villain emerges who wants to disrupt the harmony of the event. But with the help of his friends and his own heroic skills, Deku manages to defeat the villain and still have a wonderful wedding.
Their relationship with the guild leaders could become strained. The leaders might see them as irresponsible for getting left back. However, as time passes, Lisanna and Natsu could prove themselves in other ways, like taking on extra tasks around the guild to show their dedication. This could gradually change the leaders' perception of them and strengthen their relationship in the long run.
The main characters are clearly Natsu and Lisanna. Natsu is a well - known character with his fiery personality and powerful dragon - slayer magic. Lisanna is also important, she has her own set of skills and a unique relationship with Natsu.