As for the idol character, it was a serious Vanguard role with clear job divisions and unique traits within the Secret Realm. Vanguards who donned this role could indeed pursue an idol career in reality, but there were not many who did so. Due to "Secret Realm Law" restrictions, they were unable to use their enchanting Secret Abilities outside of the Secret Realm. This meant that this role did not provide any significant advantages on the path to becoming an idol, nowhere near as effective as the elves' passive Secret Powers that allowed for smooth skin and anti-aging.
As for Kaka, although he was not a professional idol, he had amassed a large following due to his varied short videos and vocal prowess. His career in the Secret Realm didn't fall behind either; he had spent years focused on the challenging Role-play Secret Realms, achieving success in both literature and sports.