Apple Books' Intensive CPU Usage

A process from Apple Books, com.apple.WebKit.WebContent is using the CPU around 99%. To the point of my mac eventually becomes warm. This doesn't make sense if reading a single book consume 99% of the cpu how would I even work? I am reading a downloaded epub Book with Apple Books on macOS 13.4 and the cpu usage is insanely high. It would be great if someone can help me with this. Thanks.