Hi there! Currently we are rated 16. There will never be nudity. In a certain ending, sex can be implied, but it is never shown or specifically stated.
Besides that, the reason for our rating is that sometimes there is distressing imagery when the girls expire - In some routes there is disfiguration and death shown (No blood, since they are mushrooms). The below screenshot might be helpful for you to determine if this game is for you. The first 3 are only in the demo, while the full list is in the full game coming out later this year.
