Annika has long blue hair and blue eyebrows. She wears a pink shirt, a purple jumper over her shirt, gray leggings, and fuchsia and white colored sneakers. She also wears several earrings and a necklace with a pink pearl. Her hair and eyebrows look very similar to Milhouse's.
- Unlike many members of Milhouse's family, Annika does not wear glasses.
- Milhouse seems to hold some sort of attraction to her, although she is his cousin.
- He claims that his parents are cousins themselves and it worked out great for them.