Guy from present is sent back to paleolithic times, but with humorous take on cliches of this kind of story. Examples:
Defeats caveman in battle and is told he inherits his defeated opponent's wives. Turns out the women are very unattractive - short, fat (probably true due to early child bearing), unclean, smell bad, missing teeth, eyes, etc. - but they force him to have sex with them.
At victory feast protagonist is enjoying the meal and asks what the meat is. Is told it's his opponent.
He finds his knowledge and modern weapons, etc. are not as effective as he thought, like in Poul Anderson's story The Man Who Came Early (summary here https://en.wikipedia.org/wiki/The_Man_Who_Came_Early).
etc., etc., etc.