No harem ending, Rusty's ending is the true ending. It feels weird that you can fuck around with every girl before her final event (ending) and the game doesn't acknowledge that you fucked all of these girls. Reminds me of Trails of Haha aka Rean Schwarzer's harem adventures.
There's a big plot revelation in Suzume's ending so I recommend you play it, most of the individual endings serve as a character development for each girl since they are pretty much irrelevant in the main quest.
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