cat and mouse

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun idiomatic A relationship in which two parties closely monitor and challenge one another in a suspicious or self-protective manner, often because each party is attempting to gain an advantage over the other.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a game for children in which the players form a circle and join hands; they raise their hands to let a player inside the circle or lower their hands to bar a second player who is chasing the first