flank (the side of one's torso) / to coerce / to threaten
胁
=
办
+
月
:
Marie Curie (xi) started a new business (办) in the elevator's kitchen (e2) offering gymnastic practice which helps to relieve tension in one's flank (胁). At first she offers the moon (月) to participate, but as the moon declines she threatens (胁) him with an impressive gymnastic move.