The characters of Howl's Moving Castle are loveable, funny, and overall characters to become invested in.
As a young woman, Sophie is intelligent and concerned about being responsible. She wants to do what her father would have wanted for her and wants to make her family proud. Though she is responsible, she also seems to be a pushover, letting others do what they want - mainly her sister.
She is harassed by two guards one day on her way to see her sister, but she is quickly rescued by Howl.
He takes her to her sister (with a small mishap) by walking on air. She is in a daze after that and tells her sister what happens.
Soon after, she heads home. The Witch of the Waste knows she has been with Howl and when Sophie doesn't give up any information, the Witch changes her into an old woman. That's when everything about her starts to change.
When Sophie is changed into an old woman, at first she couldn't believe it. She was hurting and creaking and cracking in places she never thought she would, and she has a hard time moving around. She knows the only person that can help her is Howl. So she packs a few things and heads off to find him.
Upon arriving in Howl's castle, she immediately runs into Calcifer, a fire demon.
He isn't sure what to make of Sophie, but the two quickly become friends - or at least frienemies. He doesn't trust Sophie at first, but after begging and threatening him to let her work there, he slowly warms up to her. Sort of.
She also meets Markl, a young boy who wants to become a full fledged wizard one day. He works for Howl as the chef and cleaning boy, but he doesn't do that great of a job.
He thinks that Sophie is just some crazy old lady who can't do anything, but Sophie shows that she can. She cooks, cleans the entire castle, and is truly kind to everyone there. Although, she does end up mixing potions in Howl's bathroom, causing his hair to change color.
It soon grows on him though (and it looks better on him). Howl, himself, is a wizard and fights alongside the king of his country to take down the rivaling country. It's a hard battle, and Howl transforms into a bird to do it. If he doesn't cool it down, though, his entire self would be lost to that bird creature. He did give up his heart, after all.
Each character grows and develops as people (or creatures) and discover what their true meaning and calling is for the time. They all grow together. They learn each others likes and dislikes, what it means to be in love, and what it takes to release someone from a curse. Each character develops as an individual, but each depends on another character in the movie.
The characters of Howl's Moving Castle are all a bunch of silly, loveable, growing characters that you can't help but feel something for. I personally love all the characters - even the Witch, who was the villain, but she soon grows on you. I know I didn't talk a lot about the characters individually, but I truly believe that you should experience this movie for yourself to see just what I mean. It is a fantastic movie and you'll want to watch it over and over again. Eventually you'll probably be like me and memorizing and repeating lines as you watch it.