Stitch

Stitch is a monster. He's defined as one in the very first scene of the movie. His personality and purpose are explained to be total destruction of anything he touches. Every authority figure in the film considers Stitch to be evil, grotesque, and entirely incurable of his destructive nature. Yet he is the movies primary protagonist. Stitch is an anti-hero; a villain whom the audience desires to see succeed, prosper, and ultimately change.

Stitch is one of the major examples of the "greying" of good and evil within "Lilo and Stitch". He has been created for blatantly evil purposes, to destroy everything around him and cause as much damage and frustration as possible. Yet, being presented as the focus of the films action, the audience sympathizes and cheers for Stitch, hoping that he will ultimately find freedom and peace. Disney plays on the "anti-hero" concept with Stitch, making him a good-guy by making all those against him either worse or very specific in their philosophy. He is aggressive and violent, but better than the sadistic vengefulness of Captain Gantuu. He is uncontrollable, but we prefer him to the domineering attitude of the Grand Council Woman.
The fact that most characters in the film give up on Stitch easily is one of the most religious messages in the film, perhaps aimed very particularly at Christian viewers. Lilo does not give up on him, welcoming him into her family despite his evil tendencies. I find this relates well to Biblical stories of Jesus Christ, who associated with sinners rather than giving them up for lost. The often-repeated line in the film "nobody gets left behind" can be viewed in this respect not only as a philosophy about family inclusion, but also as an evangelistic worldview.
Despite the fact that Stitch "has no place among us" we find that he does indeed have a strong need to belong. As he watches Lilo play with Nani and David on the beach, Stitch is perhaps at his loneliest. He desires to be a part of the domestic enjoyment he is seeing, but still find it difficult putting aside the monster he is designed to be. This again is a significantly religious suggestion, implying that even those outside of the church have a need to belong in it.