"Uh huh..." For once, Peter was being absentminded, rather then paying great deals of attention to how he was behaving, or just what was being said. Under a cloak that was simple enough to understand. After all, it did make the wearer invisible.
At Lily's exclamation, Peter flinched, the slightest movement, and pulled his eyes from the spot he was scrutinizing, to where she pointed. It was someone. Who he could not be sure, yet it made no sense to just ignore it!
"Y--yeah, we should..." Carefully, he eased the door open wider and slipped out, waiting for Lily to come along, all the while watching the person drawing ever closer to the edge of the Forbidden Forest.