I just noticed that her eye color changes whenever she is worried/nervous ? her right eye becomes violet whenever you talk to the 3 men. You can see her eye color change when the 3 men talk about reward or when she is nervous about John not winning.
her eye color changes first changes when she talks to the chief in the intro after drinking what ouichi gives them. The first choice you get in intro also changes her eye color depending on your answer(Support the wife and saying you will do anything to get flower will not change her eye but saying "i don't know" does). It also changes when trials are mentioned
I don't think she was born with heterochromia, it has to do with the goddess. Just like his comic version girl who got heterochromia after her possesion. So if it, i gotta say whatever they gave her works fast.
Honestly the vanilla route is better, Has some of the hotter CGs too. Also by the looks of it, she doesn't like doing it with other men. She gets cursed and only gives up if the MC is weak or cheats on her. If you remove the ntr aspect, this plot could be a b grade hollywood movie where Research guy and his wife search for cure and save the world. Lmao reminds me of Green hell game too