not a day goes by where i dont think about the Eas vs Peach battle so
this moment is very fun to me because when i first saw it, it seemed kinda strange for Setsuna to place her made up prediction as some kind of a turning point in Love's life. i mean, "get your happiness" was her catchphrase from way before even meeting Setsuna and in general Love is a happy go lucky type of a person. and that is until you remember
it's Love who often points it out as a sign of her happiness
i dont have better screenshot on hand at the moment but iirc she says it a few times while with Setsuna. for Love Setsuna's prediction did mark the beginning of her happiness
and all of it amounts to Setsuna being a centerpiece, a sign of Love's happiness
The red heart is a symbol of happiness.