thats understandable but you have to understand the market why would someone get a vn for $15 when they could get something of similar if not longer length and slightly worse quality for cheaper or free.
like i understand your trying to monetize a hobby or maybe you treat this as a job but at the end of the day your making a adult visual novel, not exactly the most prestigious industry. in my opinion at least, one would have to make a seriously awesome VN for it to even warrant a price tag let alone $15.