Has anyone ever won the game without using cheats? Mind you, with cheats still seems a long path to victory, but I guess it will be doable, in the end. But without cheats?? Even abusing some loopholes (red light street to get back energy and other minor tricks) it doesn't seem feasible to me, even with the RNG God on my side.
It's doable, it's just insanely grindy and results in a lot of months where you aren't doing anything other than just building up.
Basically, you have to focus on "losing well" for a long time, because in the process of losing you can get a bunch of energy or money or blackmail that you then use to go and accomplish other things.
I mean, the idea here is that you start out severely outmatched and outgunned, and later on you can turn the tables by degrading her cards until you're in a position to start trouncing her.
The problems with that:
1. Crushingly losing every game to start is not terribly fun.
2. There's a midgame where it is possible (and a bit later, even easy) to win, but where it's actually more advantageous to lose. Why? Well, losing gets you stuff that you need to further degrade her cards. Winning gets you glory--or victory points, but doesn't really help much with the business of dragging her down/seeing more of the sex content.
3. Eventually the card game is just a thing that gets in the way of the actual fun. The cheat I'm most inclined to use is simply the "skip card battles" cheat.
The game is absolutely winnable without cheating, it's just really grindy and unfun to do it that way, unfortunately.