you get points by:
taking off the blanket, bra, and panties.
blanket is a slow drag down with the first hand option (left one), slower the better.
bra and panties require you to move her arm and legs respecitively, the smaller buttons on the left side above the big 3 position buttons. then click many times with the first hand action until both are fully gone.
making her cum
once all clothing is removed you can start building pleasure, use the pointing finger (right hand option) on her pussy until the heart meter is about 1/3rd full, then use the grabby hand (middle option) instead. once the meter is 2/3rds full you can use the kiss mouth (left option) until the meter is about 3/4ths full, then use the tongue until the screen flashes pink.
do this twice in a night to get 30 points. this should be fairly possible even with only a level 2/3 in all stats, so go for this earlier to max stats sooner.
making her cum, and not failing the night by waking her up, gives a normal ending where she looks happy instead of shocked.
cumming on/in her
once youre godlike at getting her meter full without wasting more than half your time or sleep, you can start fucking her. click the leg move icon again to put her in missionary position. her heart meter needs to be 3/4ths full, once it is you can use the left dick option to insert into her pussy. then click again to fuck her. this will cost a decent amount of sleep (like 20%) so be saved up, it also fills about half her meter and nearly guarantees an additional cum. you can also click on her boobs or mouth with the dick to titfuck or jack off on her face. the face costs a ton of sleep as the flashlight on her face the entire time drains sleep quickly. titfuck adds about as much heart meter as the mouth actions.
being at 100% cum meter when any of these actions are done will cause you to cum on her, with an option for creampie if done in the pussy. however the mouth and tits will also cum if you hit 100% as a result of the action, the pussy will simply end the action and leave you at 100+% without cumming.
the more you unique places cum on/in her, including anal actions in the third position, the more points you get.
note, each time she cums her meter will reset to a higher level, after 4 or 5 times you can fuck her nonstop without triggering instant bad ending without any foreplay inbetween fucking.
also click the lower part of the bed with the dick option to jack off, raises cum meter without affecting sleep meter. you'll need this for 4+ cumshots as the cum meter fills very slowly compared to sleep meter draining.
idk what exactly triggered it, but i got a good ending after a marathon night where i came on her face, titis, stomach, and creampied her pussy and ass, then didn't wake her up but let the time run out instead. the image had her looking very happy.
sadly though i didnt see any unlocked options from the good ending, usually these kinda games unlock a free play mode where you no longer need to care about the sleep meter, but i couldnt find it here.
stats appear to be, but i may have the exact names wrong.
skill - im assuming this is pleasure per action, but unsure
sleep - extra 10% sleep at the start of the night
action - time limit
care - amount of sleep lost when acting
vision - size of flashlight circle and darkness of surrounding room