Given its use, Yasuho intends to create a pull down chalkboard, or paint over one of her doors somehow, so that it's easier to access certain gates.
A bucket of sidewalk chalk that when you draw a door with it you can make a portal that'll take you to any available gates (meaning current plot gate or the stable gates).
Dimension Chalk
A bucket of sidewalk chalk that when you draw a door with it you can make a portal that'll take you to any available gates (meaning current plot gate or the stable gates).