If you surrender to an enemy, they will either knock you out, demand you to give them gold or force you to a weight gain event. Unless of course, the enemy doesn’t accept it, and the battle continues on. Let’s say if you surrender to Succumbus, she will make you fatter, hypnotize you, etc.
I suppose I could implement that. The “Wait” action already exists so I don’t so the harm in a “Surrender” action as well. Though because I’m lazy to write dialog I probably will make most enemies continue fighting if you attempt to surrender unless it would lead to a sexy scene like with the succubus. 
Yeah, I think the “wait” option does pretty much that.
Maybe if you die of “waiting” some enemies could steal money or some object in your inventory?