Before you install, Greasy Fork would like you to know that this script contains antifeatures, which are things there for the script author's benefit, rather than yours.
This script is only fully functional after you make a payment. Greasy Fork is not involved in the payment, so can't validate you will get anything of value or help you get a refund.
The author of this script explains:
主脚本（Reading mode for mobile）为付费脚本