It seems like he gave her bigger breasts than he did in the tank. While I like busty girls Tamagoro does use them a lot so I would rather him stick to using different body types.
Part of the appeal of these kind of sets is seeing different girls go through the same thing, but this might be a little too similar to the one with Kirara. Tamagoro could have had Runa put her arms behind her head in panel 3, and given her a different expression in panel 4.