You can permanently delete your Foxy account from inside the app. Here's how.
Steps
Open your Profile menu (top-right avatar).
Tap your email address at the top of the menu.
On the My account page, scroll down to Delete account.
Confirm the deletion.
What happens when you delete your account
Your account, characters, and generated content are permanently removed
Any unused credits are forfeited
You'll need to sign up again if you'd like to return
If you have an active subscription, cancel it first via Profile menu → Subscription & Billing → Cancel subscription.
If you'd prefer to keep your account but pause spending, you can simply cancel your subscription instead — your credits and characters stay safe, and you can resubscribe anytime.