What does it mean if there are bite marks on your Leopard Gecko's neck?

These are the preliminary signs to separate the geckos. During breeding season, males will grab onto the females neck during intercourse in order to hold her in place. Sometimes a male can leave behind wounds. If the female has lost interest in food and is hiding away more so than usual, she may be stressed from the males aggressive behaviour. Sometimes even during breeding season, females will have to be separated to ensure her health isn't put at risk. If two males are housed together, these bite marks will stay consistent until one slowly passes.