Thanks to some good advice form Jaxxxs and LewdPooh, I tried RPG Maker VX. Since the program does all the game work for you I only had to draw the art, and consequently, after 1 month I have 3 functioning sex events already. The downside is the maps and sprites look the same for ever RPG Maker game (as seen below), but I will look into replacing them with my own art (months of work) in any 'serious' future release.
I'm thinking about releasing a fun 'test' project once I have enough scenes for a functioning storyline. One improvement is the ease of using multiple layers and choice-paths to create different clothing and sex activities. I will show a few screenshots here:
You can undress the actors in the scene by using your Seduction Points (MP). Energy (HP) decreases from sex.
Multiple layers (16 used so far) allow user-customizable clothing/sex options.
Body sizes are also cutomizable. Here the bum size is large and breast size is medium.
That's it for now. Depending on work and school it'll be a few months before I release this next project.