吉
=
口
+
士
:
Mnemonic symbol: "Giga" apparently stems from a Greek word for "giant", so I'll represent 吉 by a giant.
The giant (吉) just entered the space station's kitchen (Ø2) and is very hungry. In each hand he holds Joan of Arc (ji) and the bachelor (士) captive and robs them for their mandarins (口) which he longs for.
士
=
十
+
一
:
Sherlock Holmes (sh) is meeting the bachelor (士) in the bathroom of the space station (Ø4). Sherlock Holmes is playing a flute (一) for him, and the bachelor is wearing a huge cross (十) around his neck.