Mako-chan Kaihatsu Nikki

This event sets the stage for the entire series. Takeshi is depicted as a manipulative and calculating individual. Rather than scolding her, he sees an opportunity. He begins a campaign of sexual blackmail and manipulation, preying on her guilt and inexperience to coerce her into sexual acts. The primary motivation for Takeshi's actions appears to be a sadistic desire to "corrupt" and "train" his stepsister, as well as an underlying jealousy that she has found a boyfriend. The series' title, "Development Diary," is a literal reference to Takeshi's secret "journal," where he meticulously documents and plans his systematic psychological and physical corruption of Makoto.

The final major release incorporated all patches and fan-requested features, including a "pure route" expansion and additional diary entries. This version is considered the definitive experience by most fans. Mako-chan Kaihatsu Nikki