Usagi is arguing with Chibiusa over who gets to hang out with Mamoru for the afternoon.

Although Episode 141 is a humorous filler episode largely centered on MInako, it's the introduction to the episode that I find particularly funny. Usagi and her daughter from the future, Chibiusa, are playing tug of war over Mamoru's body, each one insisting that it's there turn to spend the afternoon with him. Of course, after two seasons, Mamoru has learned that it's best to not say anything when the girls are arguing over him.

From Episode 141 - "Koi no Arashi! Minako no Futamata Daisakusen" (A Love Storm! Minako's Big Two-Timing Project).