artists_beware | Looking for advice (Reply)

I have recently run into a problem with a commission I just did. I know it may be too soon to jump to conclusions but I don't know how to handle this.
I have never had a customer come back to me saying they were unhappy with a purchase. But today I received this email

Okay, I just got them in the mail. I tried them on and am sad to say
that I am really not happy with the purchase. The ears are headache
inducing and the tail just will not stay on the belt right. Is there
anyway I can send these back and get a refund from you?

I really don't know how to go about this, there is nothing wrong with the tail, no holes, it is structurally sound, not damaged. I know alot of husky tails flop over, I really don't know how to remedy this, also I told the customer the ears would be on a headband. I guess what I am asking is the customer right to ask for a refund? This almost sounds like buyers remorse. It states in my TOS
"50% (non refundable) of the total up front for hoodies, bags, or tails so I can purchase supplies." How much water does a TOS hold? Also what is stopping the person from opening a paypal dispute and forcing me to refund the whole purchase price? Am I responsible for shipping back to me?
The set in question-
http://www.furaffinity.net/view/8105621/

EDIT:
I sent them this email yesterday morning ( I did not want to wait to long and have them think I was ignoring them)

Hello,

I am terribly sorry that you are not happy with your items. I will gladly refund you 50% not including shipping to you or back to me, which would be $35.00, which is a little more than 50%. I will issue the money back to your payal when the tail and ears get back to me in satisfactory condition. My refund policy is clearly stated in my TOS here http://www.furaffinity.net/journal/2527007/. My TOS is also very similar to other makers, and quite standard. I also reserve the right to resell the tail and ears at my discretion.

If these terms are not acceptable you are more than welcome to resell it privately or on furbuy.com . I will take your comments into consideration going forward.

Please let me know what you decide,

Thank you and have a good weekend,
(My real name)

I have yet to hear back from them. I will update this post as new info comes available. I thank you all sincerely for the suggestions and after reading though them it looks like I made a good choice with wording this email.