Yes, I studied Japanese language for one year in Tokyo when I lived as an exchange student there. I also continued my study in my country's University and on my personal time. I did translations for some fansubs back when they were a thing, including Gotwoot Subs, actually. I also translated manga and sound episodes for fun for a while. Since I mostly consume Japanese media, I never really got rusty and only expanded my vocabulary and cultural understanding since.
I am sincerely not backing any argument in the thread. I just felt I needed to provide the most accurate translation of that monologue.
WN means Web Novel, which was the original material from the author until he published it in LN format. WNs are usually hosted in a web novel posting site, and the chapters are usually released one at a time, like a serialized story.
It is also very common for language and story to be toned down in LN vs WN. WNs basically have no editors and very little rules about their content. LNs will have to submit to the rules of the publisher and their market regulations.