Chelsey and Kelsey are fraternal twin sisters of Leonard's class. They're two of Leslie's best friends and secret admirers of Scott Leadready II. They think they're better than everyone and constantly fight with each other. They are usually seen fighting with each other because they are both popular and competitive with each other. They also enjoy hanging out with Leslie and Younghee who are their best friends. However, they are secretly are jealous of Leslie's smarts and her rich life.
- Chelsey and Kelsey share the many traits, roles, qualities, and voice actor of Tessa and Vanessa James of Pepper Ann, another respective OSM show.