Are you sure? If I remember correctly fucking Ivy may have consequences with more than one girl, I'd say Ashley AND Carol at least, maybe Yuki or Sara.
maybe I forget to fuck her on a path or 2 to test the waters but out of all the saves ive played only had consequences for 1 girl but maybe I made a mistake. As I did confuse myself quite a bit with my saves and pathing in this game. I intend to redo all my saves at some point.
On my initial playthrough I didn't have an issue with any LI as a result of
fucking Ivy. On that playthrough I wasn't involved with Roxy (somehow - I think I went too far initially without the points to back it up), Ashley (didn't have the intelligence to "save her", but this is definitely the one that
fucking Ivy will nuke), Nikki (didn't chat with her at the first party), and Natalie (didn't (don't) like her).
Unless I missed something, or it came up in the latest update, Carol, Yuki, and Sara were all fine for me (and Rachel too, but it's like she exists in a different universe when it comes to this stuff anyway).