Quirky (adjective)

1. Having or characterized by peculiar or unexpected traits.
2. Eccentric or unconventional.

Origin:

1840–50, americanism; perhaps akin to quirk.

Examples:

1. The house had a quirky design with sloping walls and irregular shaped rooms.
2. She had a quirky sense of humor and always made her friends laugh.
3. The movie had a quirky plot that kept the audience guessing.
4. The restaurant had a quirky atmosphere with mismatched furniture and dim lighting.
5. He had a quirky habit of humming to himself when he was working.