This is for over the shoulder of character 2:
BG1
CHAR1 stands screen left AND CHAR1 faces right AND CHAR1 moves to layer 1
CHAR2 stands screen right AND CHAR2 faces right AND CHAR2 moves to layer 2 AND CHAR2 is rear
This is for over the shoulder of character 1:
BG2
CHAR2 stands screen left AND CHAR2 faces right AND CHAR2 moves to layer 1
CHAR1 stands screen right AND CHAR1 faces right AND CHAR1 moves to layer 2 AND CHAR1 is rear