People here are not much better tbh. Clamouring for her to be part of the 'Sanghyun's harem' is mad weird.
Yeah I think its more admiration she looks up to Yoil and thinks she's cool.
To her Yoil is the super cool woman Mooyoung aspires to be. In that way Yoilis already succeding as an idol
In the last chapter she was like 'Yoil unnie gets it', she knows Yoil is the cool type, but was surprised when her Oishi was not as she thought.
Thats more a fan attitude she was projecting her own image onto Yoil, like Mommy Yuyeon mentioned fans will do. And fans can get flustered by their Oishis hence her running when she got close.
I'd say in reality only Iruha and So-ae are into Sanghyun...Oh Mimji was joking to Yoil (i think), and Dabi is similar to Mooyoung she thinks Yoil is a cool beauty.
Admiration is not the same as romantic interest, but can still lead to people getting flustered.