There's 5 endings that I know of.
1st: After getting tied up by the robot initially go into the kitchen and try to use the scissors 3 times. The Robot will say "SHARP OBJECTS ARE NOT ALLOWED!". This gets you the hogtied ending.
2nd: After using the sink in the bathroom to remove the tape from your hands and then talking to the ghost in the closet, get the red lingerie from the drawers next to the bed in the main room, specifically under the "HEXy" sign. Speak with the ghost and it'll accuse you of ripping it off. So talk to it three times and this gets you the ghost toy box ending.
3rd: You find all three pairs of panties from the drawers directly above the punching bag, the drawer under the HEXy sign, and in the washing machine in the bathroom. Give them to the ghost and it'll lock itself in the bathroom. Before trying anything else go back to the drawers under the HEXy sign where you found the red panties and examine the tablet. The robot will say "WARNING- CHANCE OF ELECTRICAL SHOCK!" and add bindings. Do this three times and get the voodoo doll ending.
4th: After finding the voodoo doll under the sink and using it to short circuit the electrical box in the closet, examine the dumbell on the floor next to the robot. The robot will say "--ERROR-- OSHA HAZARD" and add bindings. Do this three times for the schoolgirl outfit ending.
5th and final ending: Get the clothes hangar out of the closet behind the skeleton and use it to get the scissors out of the washing machine in the bathroom. Then attempt to walk out the front door. This automatically gets you the straight jacket ending.
That's all as far as I know so far. Short. Sweet. Fun!