It was for sale during the first few days, and then it was no more. There is nothing confusing about it. People who get it for free, often pay for it, anyhow. This was the first release and I want it to be seen, tried, and played by as many people as possible.
Let me save you some time and answer in general. If the character has a name input (where you decide their name) that is what I consider the main cast character(s). Main cast stays with you all the time and is also considered Li (love interest) later on in the game (should you choose it). It's just that it takes a little or a lot longer in order to get there with the main cast. So, yes. Lilith is also on the list. Just not right away kind of thing.