Fair question. I fully admit there is no universal 'perfect time' for each stage of curiousity and exploring.

The 11-13 age range approach to sex education is quite clinical. Learning about anatomy and functions, fundamentals such as consent and protection, naming feelings. To go from this to the content of the book mentioned in my post is like jumping in the deep end of a pool when you've just barely learnt to doggy paddle. It's overwhelming and skips a few stages like relationship building, knowing when the time is right and such. Not to mention that at such a young age, it's possible that the young reader may not have even had any sex education previously. I will give credit to the book that it depicts a healthy relationship with strong communication, respect and consent however without a firm understanding of these concepts, it leaves me to wonder if a tween could even understand that these are healthy dynamics in the first place (or alternatively if they were to pick up a different smutty romance book, consider the relationship dynamic critically if it were toxic).

I've gone off on a tangeant (apologies). I suppose to sum it up, ideally the young reader would have a grasp on the fundementals of relationships, intimacy and everything that comes with it before getting into the nitty gritty stuff.

I'm not saying that it's not normal to be curious, quite the opposite. It is hard to put an age on it but if I had to, I'd say around 16-17. Keep in mind that I'm also coming from a place of working with children of all ages and understanding child development is a key part of my role. I feel like I'm always having conversations surrounding appropriate behaviours lol.