She's not a saint, she's just a complete dumbass who does all this because she feels she's supposed to, because it fits her role as the class president or whatever.
At this point I'm 100% convinced Hikari got dropped on her head a couple of times when she was an infant. Like genuinely, every thing she does is somehow more stupid than the previous and this just takes the cake. You wanna reconnect with Aya and you take her to a hot spring, okay. Kind of...
Love how there's still so many "holier than thou" types chastising Ayami when they'd jump at the opportunity if a girl ever offered herself to them. Truly peak internet content.