Publisher: Nanashi no Rakugaki-jo
A series of breakout games using the B2 Java applet. This circle releases new editions every year with girls from anime series released during that year, in games which you use a block-breaking game to knock off their clothes. At the time of this article's posting, there are 9 "acts" with lots of girls in each release. We're not going to list every single release since it would be kind of redundant, but these screenshots were taken from Datsuburo! Act 4.
All of the games in this series are available from DLsite! The banner link will take you to the page for Act 1.