Hearted @LookingOswald.
What is the 4th wall? You mean getting to know the person on a much deeper level beyond sex talk?
Interestingly, I agree with your platonic love. However, there might be a time you get caught off guard -- that what you wanted was a sexual relationship (as a guest) and then, friendship, goes differently in order. That is, you become friends and then, you realize you've fallen fast and hard. At that point, it becomes normal relations with a person.
Then, there's the likes of our favorite in C. She is simply a joy to be with and people seem to have high regard for her. E is the ultimate friend and confidant, at least, to me. At times, I play that role for her. What's also great about E is no strings attached maybe because from the get go, you sense there's a wall so high that she has erected.
Anyway, see you around.