This game is in the "Devil Pact" subgenre. An unassuming guy is chosen or makes a deal with a supernatural being whom has dominion over lust. They are tasked with the mission to fuck tons of hot chicks. They get some magical gifts, like a big cock, mind powers, physical strength, etc, and these are usually balanced out by being beholden to their patron devil, as well as their supernaturally enhanced libido.
The beginning of the story takes place in the version .04 package you can download. Since this is such a rote take on the premise, it can be directly compared to a lot of others of its kind. The author isn't interested in foreplay, pretense, much less contrivance for anything to feel authentic or feasible. A lust god appears before you and says "hey you're that guy now", and then you're that guy. Your "caretaker", who is supposed to be in her 30s, looks the same age as the MC. She sees the titular big balls and immediately goes into porn logic (i.e. "boy your balls are strangely big, can I please fondle them for medical reason. oh you came on me teehee"). Then she instantly is on board with being your cocksleeve to "help you". There doesn't feel like there's any friction to the story.
There's a few random characters, but they're literally called "rando", as well as a few forgettable ladies that have big tits/asses. I started skipping dialouge, because despite being in coherent English, it felt like a machine translation, mostly lifeless. The gameplay in the first part is non-existant. Just a visual novel. The next part has a grindy money/mana system, but I couldn't be bothered.
The graphics in the first part are rudimentary and dated, though the animation is nice, if basic. They improve marginally in the 2nd part. Overall the entire thing feels rote and doesn't really stand out in any way. I'd skip it unless you've played every other Devil Pact type porn game on here and are jonesing for another.