不在了

不 = 丆 + 卜 : Bruno Bear (bu) is setting up a wind wheel (丆) with a voodoo staff (卜) in the space station's bathroom (Ø4). He also puts a "forbidden" sign (mnemonic symbol for 不) on it, to make clear that it may not (不) be stopped.

在 = 一 + 亻 + 土 : Zorro (z) and Rosa Luxemburg (亻) exist (在) in the airplane's bathroom (ai4). Rosa is in the middle of balancing a flute (一) on her head and on a pile of clay (土). Zorro uses his rapier to inscribe "Z" into the flute, so as to mark that the pronunciation of "在" begins with "z".

了 = 乛 + 亅 : Sir Lancelot (l) has completed (了) his preparations to fight the world. There he stands ready, on top of the Elevator (e5), with a sickle (乛) and a crowbar (亅) in his hands.

了 = 乛 + 亅 : Mnemonic symbol from "to finish" and the shape of the character: a prize cup.

Li Qingzhao (li) is responsible for manufacturing a prize cup (了). She only needs to add a poetic engraving. Unfortunately, she suffers from a writer's block. In the aorta's living room (ao3), someone left a cryptic message engraved on the walls using a sickle (乛), which is still lying on the floor. Being an accomplished poet Li Qingzhao is able to understand the message clearly (了), realizes its poetic potential and starts to engrave it on the prize cup using a crowbar (亅).