Are you stuck on the first or second bad end?
I wrote up a detailed guide to get Vivi's good end here: https://noasdev.tumblr.com/post/729386878161272832/vivi-good-end-guide Hope this helps!
I wrote up a detailed guide to get Vivi's good end here: https://noasdev.tumblr.com/post/729386878161272832/vivi-good-end-guide Hope this helps!