Ah, a delightful short, but humorous, story. I presume it's a one-shot since expanding it would take quite a fair bit of elaboration.
Still a few minor corrections that hit me:
"Harry reluctantly starved ..." reads better, IMHO, as "Harry reluctantly stuffed ...". And, secondly, the Weaseley's would be asking Harry to get his trunk, not his case.
Still, 'twas a pleasureable read.