地壳

地 = 也 + 土 : Dorothy Gale (di) operates the excavator (也) in the space station's bathroom (Ø4) to move a pile of dirt (土) out of the way.

壳 = 冗 + 士 : The Queen of Hearts (qi) is dating the bachelor (士) in the aorta's bathroom (ao4). The bachelor tries to impress the Queen of Hearts and inhaled a lot of helium (冗), but instead of sounding funny he is just squealing so much that the Queen of Hearts hides under her carapace (壳).