First, it is crucial to identify that like Naruto or Attack on Titan . Instead, it is most likely a title originating from the doujinshi (self-published works) market, indie adult games (often created in RPG Maker or similar engines), or a series of illustrations posted on platforms like Pixiv or Fantia.
There are multiple episodes of the anime adaptation, often found on archival sites like the Internet Archive Visual Style: Mako-chan Kaihatsu Nikki
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