Yay! This made me laugh. :) I love this dynamic you have going among the three. Jin laughing at Mugen's confusion is priceless.

Aw, I love it! You've done a lot with few words. And with just one line of dialog each, you've captured Mugen's and Jin's characteristics nicely. I hope you'll write more, whether it be a series of drabbles/one-shots, or turning this little gem into the start of a bigger story. :)