On the title page right under the Overview, is the statement: (This game has a very complicated development history. It will never make me any money because of the incest and shota, which are banned almost everywhere. But sometimes I still feel inspired to keep going.)
Your MC could pass as 18, as is. Maybe work something into the story that he is attending college to bolster that idea. The BIGGEST reason your Incest and Drugged Mother games are likely to fail, is that they have gone basically nowhere beyond a small demo game, even after some updates. Incest is almost 3 YEARS in the making and the other, almost 1 ½ YEARS.
You have 3904 followers under the free selection in SubscribeStar. I would suggest ADDING a $1 support level with the same or similar benefits as the free level. If half or even a fourth of the free subscribers switched to the $1 level, that would double or triple your income. Maybe that extra income would allow you to devote the time desperately needed for your non-futa games, and probably turn them into money making games in their own right.
I really think you have overpriced your work, but maybe you are doing great with the futa style games. I have ZERO interest in those games, so I have nothing to base an opinion on for those games. I would be interested in supporting you, if you would make real progress in your other games.
I support about 30 developers on SubscribeStar, but only one at a $10 a month level (he produces a steady, consistent stream of quality work). Most others are at $3-5 a month levels.