For a DoriTama School event, students are arranging "exchange sleepovers" where they partner up and stay at each other's homes. Mametchi is partnered up with Coffretchi. When Coffretchi stays at Mametchi's home, Chamametchi mistakes her for a sister and later becomes delighted with her make-up hobby. When Mametchi stays at Coffretchi's home, Mamacoffretchi and Papacoffretchi does their best to keep him entertained by serving large dishes of meals.