A pack of 3, Small Matomaru-kun Erasers in neon colours.
The name translates roughly to "it gathers", and that is the whole idea. As you erase, the shavings draw together into soft clumps instead of scattering, and some cling to the eraser itself, so a single sweep clears the desk.
The compound is soft enough that graphite lifts with very little pressure, leaving the page intact rather than greyed or torn. In the small format, sleeved in neon paper bands, each one sits easily between two fingers.