"Imouto sae Ireba Ii" (all good as long as we have younger sister) volume 3 by Hirasaka Yomi. The previous two volumes were just comedy, this is the beginning of a romantic comedy.
This volume did not continue the trend of opening with a bizarre sketch of a sister novel. Instead, it starts with a brilliant miscommunication scene that sets the tone for the rest of the book. What happens in the middle is a date episode followed by a date episode followed by yet another date episode. It ends with a confession, not the typical "yes I do" type of exchange, but something even more brilliant. It was the most serious dialogue that have appeared in the this series so far.
That confession was a highlight of this volume, the other highlight (or perhaps a lowlight for some) was an improvisation game between authors who are trying to steer a parody of Attack on Titan toward the ending of their choice. The parody wasn't the highlight, it was a particular weapon that I am pretty sure would disqualify this series from being animated and broadcasted in public. This series isn't holding back at all.
There is an extra semi-serious chapter explaining why Itsuki came to have this obsession with younger sisters, tying back to the title of this series. This series is revealing more depth than I expected from the fluffiness of volume 1, I just hope that it continues to have all those pointless but entertaining games.
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