expression, ichidan verb
turn one's back; show one's back
Used literally or figuratively for turning one's back on an enemy or opponent, often implying retreat or cowardice. The expression is a fixed phrase.
敵に後ろを見せるわけにはいかない。
I can't turn my back on the enemy.
彼は戦いの最中に後ろを見せて逃
He turned his back and fled in the middle of the fight.