Ummm...🤓 Grammar police here 👮♂️🚨. Your sentence should be "How could I have made such a rookie mistake?" or "How did I make such a rookie mistake?". Thank you very much 🤓.
Not misuse since I'm using it in the context of this manga's world. Sarcasm is hard to tell through text huh?
I regret not putting some crying emojis at the end, like so:
more obvious version
or the opposite
When these type of manga are done, they should be compiled into one mega chapter, for convenience's sake. Like what they do with separate takoubon chapters on e-hentai. Having to load every 1 or 2 pages is a pain in the ass.