To write a good character in My Dress Up Darling fan fiction, start by giving them a unique quirk. For example, a character who always hums while working on dress - up dolls. Also, give them clear goals, like a character who wants to create the most beautiful doll ever to win a local competition. Their backstory is important too. Maybe they grew up in a family of doll makers and that influenced their passion.
A good character in this fan fiction should have a distinct personality. They could be shy and reserved but come alive when talking about dress - up dolls. Their relationships with other characters matter. If a character is in a friendship with someone who has different views on dolls, it can create interesting conflicts. Additionally, their appearance can be related to their love for dolls. For instance, they might always wear clothes inspired by their favorite doll designs.