Joan Griffin, also known as Joan G. is a former SDH member from 2020 to 2021. She was named after the late Joan Rivers and shares the same birthday with her (June 8). As stated, she is into British culture, as hinted by the Union Jack on her shirt, particularly music from the British Invasion, a term coined to describe a cultural phenomenon in the 1960s when rock and pop music artists from the United Kingdom and other other aspects of British culture became popular in the United States. As a result, she names The Beatles, The Who, and The Rolling Stones as her favorite bands. Apart from British music, she is also a fan of British television shows, such as Doctor Who and Mr. Bean

After the rights to use her as an SDH member were lost, as the creator of the character was Thunderbird/DayDreamBeliever67, Joan G. left the group on April 14, 2021. Her spot has been filled in by Maksim "Mac" Smirnov.