Issue with the Pool Party action not applying the Affection bonus once a girl's Affection reaches Loving. Did some tests with a save file, and the Pool Party seems to stop benefitting them at a "masterlove" of around 75.
Not sure whether this is a bug or intended behaviour, but if it's the latter it might be a good idea to make a note of it somewhere in the info for the Pool Party, so people don't get confused about why they're not able to use the Pool Party to keep their household's affection stable at higher levels.
Apologies to GrimDark if you get an email every time something goes up on this page, as I've done a TON of troubleshooting to try to figure out why my household's Affection kept backsliding from Undying when it didn't look like it should, and wound up writing and deleting a bunch of bug reports as I got more information and narrowed down where the problem was coming from (at first, I thought it was an issue with Affection loss not being reported correctly in the End of Day summary).