What is oyasumi?

"Oyasumi" is a Japanese word that translates to "good night" in English. It is commonly used as a polite way to say goodnight when going to bed or saying farewell to someone in the evening. In Japanese culture, it is considered courteous to use such expressions when ending the day or parting ways with someone at night.

Additionally, "Oyasumi" can also refer to various media and cultural references, such as songs or manga. For example, "Oyasumi Punpun" is a manga series written and illustrated by Inio Asano. It's a critically acclaimed series that deals with themes of coming-of-age, mental health, and personal struggle.

If you are referring to something else by "Oyasumi," please provide more context, and I would be happy to help with more specific information!