Dealing with and accidentally dealing with milk and skin

First, I didn’t understand what you brought from the Rambam. The one that deals with milk and nakedness is about all pleasures (or at least about prohibitions that are based on pleasure). Beyond that, the Rambam speaks about milk in both contexts, so this expansion is not important for your question. As for the question itself, it takes us to the very distinction between an accidental and a mesmerizing person. This is a very difficult question that concerns the definition of a mesmerizing person (and also his relationship with an unintended one. See K.S. Ch. 23). Simply put, an oversight in eating milk is eating it without knowing that it is milk or without knowing that milk is forbidden. To be distracted is not knowing that you are eating, or to eat inadvertently (without awareness). This is stated by Rashi Kiratot 19: Dealing with milk – such as milk and fat before it and knowing that it is milk and that it is fat and we mean
To eat fat and looked elsewhere and his hand went to the milk and ate a sweet
Milk and milk before him and he thought it was fat and he intended to eat this piece and he ate
This is not a random coincidence, we were aiming for this piece itself, but
Thinks he’s fat. And here, in halacha, you thought that “because one enjoys” covers preoccupation, meaning it makes you someone who is actually engaged in eating, or eating this thing. And yet, if you don’t know that this thing is milk, or don’t know that milk is forbidden – you are mistaken even if you enjoy it. This should be extended further, depending on the understandings of the person who benefits, and so on.