Margaret

Margaret is a female cardinal who works as a waitress in the coffee shop, across the street from the park. She's one of the few animals on the show that wear clothing. Mordecai has a major crush on her, and is always finding ways to make excuses to go to the coffee shop to see her. Margaret is voiced by Janie Haddad.

Appearance
Margaret seems to have a very similar appearance to Mordecai, however, she is red (rather than blue) and has a more curved beak. Unlike Mordecai, she doesn't have two white stripes on her arm, or black stripes on her fingers and her tail feathers. She's about the same height at Mordecai and has a very nice figure.

Mordecai
Margaret cares for Mordecai and at times stands up for him (ex. In Caffeinated Concert Tickets when Slasher insulted Mordecai she told Slasher, "Don't be such a jerk"). Much to Mordecai's chagrin, Margaret seems totally oblivious to Mordecai's feelings for her. In Do Me A Solid, Mordecai made her laugh however, minutes later, Mordecai spat in her face (from eating a super spicy burrito), and she seemed a little upset proclaiming, "Its okay. I don't even like this top." Later in the same episode when they went to the movies, Mordecai asked her for five bucks for popcorn and she seemed annoyed by this. When they arrived at the house later, Rigby requested Mordecai to do a very embarrassing soild that he denied to do; however, when chaos ensues, Margaret tells Mordecai that she does solids for Eileen all the time and the only reason she went on the double date was because she was doing a solid for Eileen so Eileen can be with Rigby. In this case, Margaret has no sign of love for Mordecai but as seen in Mordecai and the Rigbys the future Mordecai refuses to admit whether or not he dates Margaret in the future yet she has several other boyfriends like Slasher and Angel (Mordecai and the Rigbys). Although she has many boyfriends, it seems that she breaks up with with one of them in each episode she appears.

Rigby
Margaret considers Rigby funny (It's Time) and in that same episode, she almost went on a date with him.

Eileen
Apparently Margaret and Eileen are best friends the way Mordecai and Rigby are but little is known about their relationship. It is clear that she is close to Eileen and does solids for her all the time, as seen in Do Me A Solid. She hopes for Eileen and Rigby to become closer.