I looked into the code: typical of the type of issues I usually have with coding, it's because I typed 'Ovirgin == False' instead of 'Ovirgin = False' . I've corrected and tested it so it should be working now - just waiting for Itch to upload (a very slow process).
I think I probably prefer the corrupt Ollin route as well and I wrote that one last so the writing is possibly better than Atreus route - Atreus hits a very specific type of transformation kink though ('person turns into monster', as opposed to 'person goes sex-crazed') so there are probably people out there who prefer Atreus too.