It called HoneySelect.
It's actually a game itself, but nobody playing it. Usually it using for image generation for vn's or comics as it contains a proper editor. You could find a version packed with modes and assets here, also a huge community where you could find any answer is here. The engine for making visual novels is RenPy.
I wish you to be the next top-notch artist on Itch and will be happy to test and play your games :)