A month of being reachable from every direction can leave the mind with no edge at all, open to whatever arrives.

Blue-green with a quicksilver line, faintly iridescent. It has the cool of smooth glass under the hand, the scent of cut grass and ozone, and the taste of cold lemon.

A boundaryless mind feels like being available; mostly it just leaves you overrun. The sigil blocks nothing and filters nothing — it holds a deep, clear edge around your attention, so being reachable doesn't have to mean having no inside left.