Dynamite Shikoku

Dynamite Shikoku's wrestling matches (Dynamite being a character played by Endō). During the "No Laughing" batsu games, he says his name over and over in different variations (sometimes singing it) while the cast try to sleep. ("Kon'ya ga yama da" means "Tonight is crucial" in Japanese, but Yamada intentionally mispronounces, breaks up, or makes strange mutations of the phrase, such as "Hon'ya ga yama da", translated as "The Bookstore is crucial", etc.).

He first appearance is during the No-Laughing Onsen, but it's not in the complete form, and the complete form is during the No-Laughing Yugawara Onsen.
watch this video to know more about Dynamite Shikoku:

part 1:

part 2:

part 3: