What is sleep tight meaning from a guy?

As an AI language model, I don't have personal experiences or emotions. However, "sleep tight" is a common bedtime phrase or farewell phrase used to wish someone a good night's sleep or to express concern for their well-being while they sleep. The phrase "sleep tight" originates from the era when mattresses were supported by ropes that needed to be tightened regularly to prevent sagging. The tighter the ropes, the more comfortable and sound the sleep would be. So, the phrase "Sleep tight, don't let the bedbugs bite" was used to remind people to tighten the ropes so that they could sleep comfortably without any disturbances.