Here are what I've found. they're minor though, but you might want to fix 'em ^^

‘You have do something in return.’ the dwarf leader said. ‘Cook and clean for us.’
should be 'You have to do something in return.' ne? ^^;;

’Nani?! You should be owed by my prowess!’
'owed' should be 'awed' ne? ^^;;

‘You believe me know?’
should be 'you believe me now

‘To bad for you that I’m the main character of this story.’
should be too bad for you....

‘And who is ‘we’?’
should be 'who are 'we'?'


And you mention Jirou Akutagawa (first name first) but you mentioned Tezuka kunimitsu (last name first)
I think you should decide which format you want to use, just to be consistent ^^