I'm, um, not entirely sure how that would be a spoiler, but we'll roll with it.
Anyways, it is quite an interesting hint, not at all unlike those coming from Oscar and Andi, Lyra, and Miette before them. The thing is that May, Dawn and Lana all denied having a romantic interest in Ash. Sure, that absurd blush might certainly suggest otherwise, but complete absurdity and being over the top is the entire point of the Sun and Moon series. Serena, on the other hand, never actually denied it when Miette accused her of having a crush. That's where the difference lies between Serena and Miette, and everyone else that came before and after at this point.
Let's say it was my way to "hide" what I meant with the asterisk hehehe