I found this site while googling that contains detailed walkthroughs for all character events in the game -
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This might be maintained by the dev I am not sure, but it sure contains all the information you need upfront for all girls in the game. The walkthrough mentioned in the OP is opening a file with very little information so I thought of adding this here in case it helps anybody.
Tl;Dr this can be used as a full-fledged walkthrough guide -
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