It’s very easy to forget but, on page 20 in the bottom right panel, you can see the vast difference between the three of them. And most importantly, you can see how big and wide Hakari’s hips are. We normally don’t get full body shots, let alone bottom half shots, so seeing it like this, with Karane and Shizuka as points of comparison. It really hits home just how big she is.
She’s also intentionally keeping her skirt a little short, and her clothes emphasize her breasts and waist quite a bit too. This is all intentional on her part, but they are 100% real so she isn’t really lying for appearances like she is with her attitude and personality. She doesn’t do it with malicious intent, she only does it because she thinks she needs to, she’s gotta use that “Mwehehe” charm of her’s to get Rentarou’s attention after all.