It's been mentioned before that besides Shihori and Yuri, Chihiro Inoue may also have bigger breasts than Hinako even though Chihiro is shorter, shorter than a lot of the other characters actually. Looking at this edit/stitch (they never have that pose at the same time, in-game one of the always has her arm raised covering her chest)...that may be the case, Chihiro's breasts really are bigger than Hinako's, probably.

I plan to post a variant of this image later