In the image of the girl, I find her features as oriental and in my opinion there are oriental girls who look like they are girls despite being already adults over 18, I do not know how it affects them that the characters of a game are see as children, the bad thing would be that the director put real pictures of the characters and these were under 18, but if they are drawings made by her or taking sketches of some anime characters I see nothing wrong, everyone is free to imagine what you like and I think that if some people are upset that they see no less than 18 they avoid playing the game
My congratulations for doing this type of games and I hope you can continue to develop it and have no complications that force you to abandon it, at this moment I am downloading it and I hope to start playing it, but I will wait for more updates to be able to say if the game will be to my liking
Note: I have a doubt if the girls in the images are the same or are sisters?