Came across a bug with the sister, Sam
After the christmas decorations are up and the sex scene with mom, if you enter Sam's room you end up in a never ending loop.
and if you speak to flower lady, she tells she told to go to the hotspring at night even though you've already done and if you go to the hotspring, it seems to break the game.
EDIT: actually in addition, if you enter the road where the hotel is, you get stuck and can't.
AND ANOTHER
If you enter the building opposite the mall and go into the next room you disapear.