along / to follow (a line, tradition etc) / to carry on / to trim (a border with braid, tape etc) / border / edge
沿
=
氵
+
几
+
口
:
Maud Younger (y) hides a huge mandarin (口) under a table (几) in the anthill's kitchen (an2). She doesn't want anyone to touch it, so she marks the border (沿) of the forbidden zone using water bottles (氵).