One great source could be Archive of Our Own (AO3). There are numerous well - written male reader x female reader fanfictions there. You can search by tags like 'romance' or 'adventure' within the male reader x female reader category to find stories that suit your taste.
One idea could be a story where the male reader is a trainer who discovers a female Lucario in the wild. They form an instant bond and start a journey together, facing various challenges in battles and in understanding each other's emotions.
When writing the actual story, focus on the relationship development. Show how the male and female readers start to feel about each other. Use dialogue effectively to convey their emotions. For example, if they're having an argument, make the dialogue realistic and full of tension. Also, don't forget to set the scene well. Whether it's a bustling city or a quiet countryside, the setting can enhance the mood of the story.
A lesser - known but interesting one is 'A New Beginning with Female Mewtwo'. Here, the male reader is from a small village. The female Mewtwo arrives there, injured. The male reader takes it upon himself to nurse her back to health. This leads to a series of events where they become close friends and face various challenges together in a world that doesn't always accept their relationship.
One great fanfiction in this category could be 'The Encounter with the Female Grimm'. It has an interesting plot where the male reader character stumbles upon a unique female Grimm. The story is filled with action and adventure as they interact in a post - apocalyptic RWBY world.
Self - discovery is another theme. The male reader may change and grow through his interactions with the female character. He might discover new aspects of his personality or find a new purpose in life because of her.
You can try looking on fanfiction websites like Archive of Our Own (AO3) or FanFiction.net. AO3 has a wide range of fanfictions, and you can use the search function to specifically look for 'female Broly x male reader' stories. FanFiction.net also has a large collection, but the search might need some refinement to get the exact ones you want.
Some Tumblr blogs are dedicated to sharing and discussing fanfictions. You could search for relevant tags or ask in the fanfiction communities on Tumblr. There might be some users who can point you to great 'female Pennywise x male reader' fanfictions.
Love and romance are very common themes. It's about the relationship development between the male character and the female reader - character. Another theme is adventure, where they go on exciting journeys together.
One way to develop the male reader's character is through his goals and dreams. If his goal is to become a great artist and he shares this with the female crush, it can show his ambition and passion. His insecurities can also be explored. For example, he might be insecure about his appearance compared to other guys around his crush. How he deals with these insecurities, whether he tries to improve himself in a healthy way or lets them consume him, can develop his character. Additionally, his sense of humor can be a big part of his character development. If he uses humor to break the ice with his female crush or to diffuse tense situations in their relationship, it shows his personality and can make him a more well - rounded character.