Obox/guide

Motorcycle / 二輪車
Enter the blue door. Go down then go right. Enter the red door. Enter the hole on the bottom-right. Keep entering the hole to your right on the next two platforms. When you get to a platform with three holes, pick the top-left hole. Enter the hole to your right again. Go right until you get the effect.

100cm Ruler / 100cm定規
Enter the green door. Go right and enter the dark grey door. Go right until you enter a room full of water. Go down and leave the building. Go south then go left. Interact with the white box/house to be teleported. Go right twice then enter the first door on the left. Interact with the ruler in the chairless desk.