make her dumber

Knowing the one thing Makoto valued more than Ren, Haru knew exactly what she needed to say to take her down a notch.

"You've never been the best at studying, have you? Usually scoring last in tests, correct?" Haru watched as those words seeped into Makoto's brain. Replacing most knowledge she had.

"Umm, yeah. I guess it's dif-diffy. Hard to learn," Makoto responded after a couple of seconds. Makoto slowly slouched forward, her mouth slightly ajar.

Based on her eyes, Haru could tell she hadn't become a complete idiot, but a simple question would take a while to get an acknowledgment and even longer to get an answer.