械鬥

械 = 戒 + 木 : Marie Curie (xi) finds a turning machine (机械) under a Christmas tree (木) in the elevator's bathroom (e4). Happily she proceeds to manufacture a ring (戒) for herself.

斗 = ⺀ + 十 : Mnemonic symbol: a 斗牛士 (dou4 niu2 shi4) is a matador, who will represent 斗 when used as component.

The matador (斗) and Don Quixote (d) are fighting (斗) in the outhouse's bathroom (ou4) about who may use the bathroom next. The matador yields a holy cross (十) as a weapon, while Don Quixote (d) wisely chose a blossom (⺀) to cushion the crosses' blows.