for /D %%D in (*) do (ffmpeg -hide_banner -n -r 24 -i "%%D%%2d.png" -vf mpdecimate -fps_mode passthrough -c libwebp -compression_level 6 -loop 0 -preset 3 -quality 95 "%%~nxD.webp")

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Animated GIF:[Smile] Boku to Koi Suru Ponkotsu Akuma
[スミレ] 僕と恋するポンコツアクマ。
https://e-hentai.org/g/920316/8e00ef0b35/

Event CG (PNG): [スミレ] 僕と恋するポンコツアクマ。
https://e-hentai.org/g/857275/fe448b798f/

do you have an archive where it's just the Mp4 video files themselves for added convenience? Like PixelDrain or MegaNz maybe

Base +6

I cannot provide the original images at this time. The source assets are not stored in a standard video format.
You need to download the full game, extract the AMV files with an unpacking tool, and then use https://github.com/xmoezzz/AlphaMovieDecoder/tree/master/AlphaMovieDecoderFakeOld to decode them into PNG image sequences.
After that, use FFmpeg to convert the images to your desired format at 24 fps. I recommend keeping a lossless format such as APNG or FFV1, which can be converted to other formats later without quality loss.
If anything is unclear, you can use an online AI service for assistance. If you know a better method, I'd appreciate you sharing it.

Base +12