Probably going to last 1 or 2 chapters. In the LN and WN the author did these mini stories every volume. If you where unlucky he did like 2 chapters with stuff like this. Be glad the painball (wargame) scene last chapter was only 3 pannels, because in the LN it was way longer.
This chapter remind me some doujin where MC become shota because of his Elder sister experiment then of course have incest Harem time (more than 100 or 200 page if im not wrong)🤣the artist start from M word (forget) milk?mild?or whatever i really forget