really short games with a verity of girls/customization?
Maybe
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it can be short (kind of) and there's a few different girls.
If you like forbidden101v's suggestions there's also
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and
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, possibly
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(also
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) and
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. There's a big list of similar DLSite games
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(some can be grabbed from sharing sites some unfortunately not).
Except for locked girl until you get the hang of them they're not really short though.
Just remembered
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is here (that uploader seems familiar).