I don't know about that chief. Do remember that the visual representation of boob size is made by the artist, she could be sitting on F or G cups but because of the artist's style they look smaller than they should. Besides...have you noticed that her size constantly changes throughout the manga? Even her first appearance she went from medium to small back to medium in every other panel and in his/her delusion they look on the big side......I wouldn't call them "quite big". They're not small by any means. They're rather moderate, I think. Should still perfectly fit inside one's hand without overflowing.
Dang it, seems I still cannot spell Wednesday correctly. It's just such a hard word to spell.just an FYI... it's spelled "wednesday"... I saw it once and thought it was a typo but it happened again