@RimuruTempest That's not really how that works. Chekhov's gun is a
guideline for writers. Advice, essentially, that anyone can and might choose to ignore. You have no guarantee any random author will actually follow it. Anyway, the clocktower was both introduced and used for something in the story already anyway. Several somethings, even. It's their date meetup spot, they used it to check out the view, and the writer also used it for a joke about her not even knowing what it commemorates. It's already satisfied the conditions, I'd say. The writer introduced a thing and utilized it rather than just pointlessly introduce it and never do anything with it afterward.