Starla Gutsmandottir, also known as Muscle Woman, is an obese, green woman similar in appearance to Muscle Man. She works at Icy & Hot Jewelry & Apparel. She developed a crush on Mordecai and dated two other boys as indicated by a tattoo on her lower back. When Mordecai broke up with her, she became extremely angry, destroying everything in her path, including a helicopter. She is back together with Muscle Man after he expressed his feelings towards her at the end of the episode.
Starla has had a number of relationships with different men, including Muscle Man.
Starla and Muscle Man's first relationship went on for a while. In "Trucker Hall of Fame" it is shown that their relationship went back from High School, and they were prom dates, taking a break from each other for an unknown time. They began dating again, but Starla broke up with Muscle Man once again due to the fact that he wouldn't show his feelings. After he finally complied to her wishes, they returned to each other and are currently in a relationship.
Starla's third "boyfriend". However, Mordecai did not want to be in a relationship with her, as he only wanted to get Starla and Muscle Man together. Despite wanting to kill him, Mordecai and Starla seem to be on good terms with each other.
Starla is close friends with them both as shown in The Longest Weekend.
Starla is Celia's best friend.
- Starla is the second female antagonist on Regular Show. The first one is Susan. However she is given more pro-tagonistic appearances.
- She looks like a female Muscle Man.
- As seen on her lower back tattoo, she has dated and broken up with Muscle Man twice.
- It is mentioned in "Weekend at Benson's" that she seems to like jazz music.
- She once dated an unseen guy named Steve, as seen on her tattoo.
- Part of Starla's last name makes a reference to the name Guts Man, one of Dr. Light's robots from the Mega Man series.