From their TOS:
You are able to view, change and remove your data associated with your profile. Should you choose to delete your account, please contact us at firstname.lastname@example.org and we will follow up with such request as soon as possible.
Please note that AccountKiller.com is not associated with the business listed on this page. AccountKiller provides easy-to-understand instructions and guides on how to cancel charges and relationships from the list of businesses on our site, we have no affiliation with these businesses.