So I am GMing again after a long hiatus, and a strange situation came up.
The characters had an opponent flanked in a narrow, 5-foot corridor, like this:
ABCXD
X is the opponent.
A is the Druid
B is the Druid's animal companion
C is a squishy, who should not have been there.
Opponent-X drops the squishy-C, who is now unconscious, at -2.
C is dying, misses save and bleeds to -3.
B moves up into C's space and attacks X.
A moves up and now is adjacent to C. Casts CLW for 6 points.
What happens now? B and C are in the same space, but it is neither's turn.