The series was released as a softcover comic in Japan (published around 2021 by Syueisya) and can occasionally be found on eBay or Japanese resale sites.
To unpack this query, it helps to break down the individual components: doujindesutvkanojonoimoutowanikushokuk exclusive
If a streaming platform prompts you to download a "special media player" or an .exe file to watch an exclusive video, close the tab immediately. Legitimate modern streaming uses standard HTML5 web players. The series was released as a softcover comic
If you enjoy this style of high-octane harem comedy, you might also find similar reviews or content for: Girlfriend, Girlfriend (Kanojo mo Kanojo) doujindesutvkanojonoimoutowanikushokuk exclusive
This suggests an doujinshi or fan manga where the protagonist’s girlfriend’s little sister is aggressive/forward.
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