The game was made in renpy, had a 3dcg artstyle. It starts with you finding your mom dead in a bathtub during a blizzard. You live with your sister, and later become a private detective(?). You end up investigating a convenience store robbery, and find a girl that can turn invisible. I remember a good portion of the game, but not the name and it is driving me crazy. There's also a part with some weird monsters that beat the shit out of you.