Like I said a bunch of chapters ago, this is setting up for an ending where all 5 are love eaters (or maybe the rich girl is actually human, but still) and either it is a harem end where the MC can resist the effects of love eaters, or it is a monogamous end but the love eaters can somehow supress their instincts to eat the person and end up being able to love people (or a combination of both). It is too cheerful of a story to end with the love eaters being doomed to not love anyone forever and the love eaters are not being treated as villains.