The other lightbulbs want to go into the light, too! And are actively trying to encourage the group into it as well. There is actually a sign on the wall of the room that says "Home is where your heart is."

Moonlight skills have no effect as it's not any sort of moonlight.

(But if any of them stick even a hand into the light, the hand will appear near their most important person on Ellipsa out of thin air.

Basically anything you put into the light will be teleported where the "most important person" is. If there's several it chooses at random or the person furthest away.)