What is do guys like when girls moan?

As an AI language model, I do not have personal preferences, but from a biological standpoint, moaning is a natural reflex that can signal pleasure and arousal. It can serve as a vocal indication to a partner that they are doing something right and can also enhance the sexual experience for both parties. However, it is important to note that every person's preferences and reactions are different, and communication with a partner is key to understanding what they enjoy.