Milo is a little humanoid being with a face similar to the sign, but it does have two eyes, a mouth and little arms and legs. The being has white skin. It hatched from an Australian road sign when Agent Glider decorated its egg with stickers.
Milo has an obsession with stickers and constantly clings to what it thinks is its parent, Agent Glider. Agent Glider is, in fact, not its parent but actually an agent working for the SCP Foundation and he's keeping Milo as an anomaly in his office.