* Aston Merrygold: The singer and dancer has been a fan of JLS since their early days, and has even said that he would love to join the band one day.
* Alexandra Burke: The X Factor winner is also a big fan of JLS, and has said that she thinks they are one of the best boy bands in the world.
* Olly Murs: The singer and songwriter is another JLS fan, and has even collaborated with the band on a number of occasions.
* Marvin Humes: The presenter and radio DJ is also a big fan of JLS, and has said that he would love to see them reunite one day.
Ultimately, it is up to each individual to decide who they think is JLS's number one fan. However, there is no doubt that the band has a lot of fans who love and support them.