I can clearly picture it.
Several chapters (and unspecified in-universe amount of time) later. Kaoruko and several scientists, in a lab, wearing white coats, surrounding a single flask of dark liquid.
"Finally, we perfected the Giant Girl formula! Now nobody will dare to laugh at me being short!"
She drinks the whole flask in one go. Instantly grows huge. Lab's roof collapses, scientist scatter around, screaming.
Kaouruko picks up a comically large measuring tape just conveniently lying nearby (made by the Department, of course).
Measures her height.
...It's 6 meters.