哨
=
口
+
肖
:
The little prince (肖) took a part time job working as a sentry (哨) for Sherlock Holmes (sh). In the aortas's bathroom (ao4) he whistles (哨), thereby giving the secret signal to Sherlock. Sherlock answers by holding up a mandarin (口), which is the secret signal of acknowledgement.
肖
=
⺌
+
月
:
The aloe vera on the moon resembles the rose on the little prince's planet. Thus I'll represent this character by the little prince.
In the aorta's bathroom, the little prince misses his asteroid and his rose so much. To comfort him, Marie Curie gives him a moon and an aloe vera to remind him of home.