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StarTropes
Since: May, 2014

Alice does something that would be considered morally good. Unfortunately, it turns out to be a Cruel Mercy, completely unintentionally on her part.
Theres A Hair In My Dirt has Harriet constantly screwing up the ecosystem out of well-intentioned ignorance (feeding invasive species, dropping a tortoise in a pond, putting a bird back in its nest where its sibling pushes it out again, killing a snake that was about to eat the mouse, etc.) that ends up killing her (the mouse had a virus on its fur).