First part of the game is horrendously slow. Click the panty screen to change view. Basically you just move close to her but not where you face her and touch her butt or thigh. Do this do this for x times then face her and start touching her thigh. When the bar starts to creep to the end switch to the next one and repeat till you can move to the next one.
Don't get anxious and try to go too fast or you'll get caught and it'll switch to the next day. When you first start out it should be butt/thighs not facing her. Anything else will make her bar goes go so fast it'll make your head spin. After a bit you can set it and forget it while it's running in the background just don't totally forget it. I was doing this while updating threads. If something happens between saves that messed things up you can close the game and reload the save as the save file is auto saved at the end of each morning and night scene so if you close the game and reload it any bad shit is gone.
Around 40 you can face her and touch her without it going super fast. The main bar you need to worry about is the pleasure bar as the more it's full the more the chance the bar might not fill up as fast or fill at all. By around 50 the bar starts moving slower. When the pleasure bar fills up anal insertion will appear then you can use the vibrator and anal sex at the same time as well as playing with her tits. Keep in mind that what you can do at night doesn't mean you'll be able to do that to her in the morning. Like having her face you in the morning will make her bar go up but at night it might not go up. By day 9 I was able to have sex with her but it took 4 or 5 more days before I was able get her pregnant as it depends on her sensitivity and climax bar.
Pretty good game - quite short and a little bit grindy.
You have to endure this slow progress just little, but in the end good ending - and custom mod will be available for you