Luna had not gone unnoticed by Sailor Moon's enemies when she gave out advice (see: nagging) during battles. During one such fight, another monster created in the image of a snake slithered its tail around her and put the squeeze on her.
Usagi Tsukino was complete oblivious to the plight of her mentor as Luna couldn't breath, let alone speak. All she could do was look at the hungry expression all over the python's face. However, it wasn't about to consume her just yet. Not before seeing how much punishment his coils could dole out.