>actually, "reflect upon your actions inside dosu's anyaru" "hansei shite" is commonly used as a demand for apology, rather than a demand for repentance.
As for the "inside" part, you might be right. The "de" particle's use confuses me sometimes.
be that as it may, in my experience with the phrase's usage in yukkuri lingo, it's more commonly used as I have said: when commanded to 反省, an apology is usually insufficient, unless followed by an explanation of your understanding of why you needed to apologize in the first place. the fact that the one to reflect is typically secluded, as in this case, further reinforces that reading.
for example, see post #4592 . can you point to an example on this site where it's clearly used as you say?
Wasn't talking about yukkuri lingo. That's how I hear it most commonly used by native Japanese speakers I interact with.
Still, the way you've explained it makes much more sense here. Sort of a "go to your room and think about what you did!" except the speaker isn't the target's parental figure.
Perhaps this would work better: "Stupid Mister Human should just sit in Dosu's anyus and think about what he did, easy!!"