Stitch
Obviously, Stitch is Lilo's best friend throughout the entire film. In the beginning, he disguises himself as a dog and takes advantage of Lilo by using her as a sheild from Jumba and Pleakly. In time, Lilo unlocks Stitch's heart with her compassion and he becomes a sympathetic creature instead of a destruction machine.

Nani
Nani is Lilo's older sister who struggles everyday with all of her effort to keep her younger sister from being taken away. Lilo, however, does not fully understand this and only accomplishes to get her in trouble with Cobra Bubbles. In my opinion, the association between these two character was so authentic ... their relationship immediately resembled the bond between my own sister and me. Even though they quarrel quite a bit, deep down inside, they truley love each other.

David
David is a genuine friend of both Nani and Lilo's. He acts somewhat like a father figure to Lilo, taking her out to surf the waves on the beach and comforting her and Nani when he hears that they had and unfortunate day. He even offers help when he hears that Lilo was going to be taken away and finds Nani a job, hoping that if she was employed, Lilo wouldn't be taken away. In the past, Nani and he were dating but due to her newfound responsibilities with Lilo, they decided to remain good friends.

Pleakly
Pleakly strives to keep Jumba from creating a riot on the weak defenseless planet we call Earth and from shooting Lilo, claiming that she was part of the mosquito food chain. He becomes part of her 'ohana in the end.

Jumba
Not much to say about Jumba and Lilo except that he finds the fact that Stitch is using a mere little girl as a sheild is ridiculous and insulting.

Cobra Bubbles
I honestly don't consider Cobra Bubbles as a "bad guy", per se ... he is just doing his job and that is to confirm Nani's capability to nurture Lilo. In spite of his massive size and deep voice, Lilo does not seem intimidated of him at all. When she first meets him, she even grows suspicous and asks him if he had ever killed anyone. Mr. Bubbles is truley sympathetic at heart and only wishes that our favorite little girl is settled with a loving family.

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