It's verrrrrrrry slow burn, but I love that about it.
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They first broach the topic of dating about 30 chapters before the end of the main story, inside the great dungeon, and aren't officially together until after it's clear. It seems like a long wait but IMO it's worth it, the connection is really deep when you finally get there. You get more of their relationship in the side stories.

Novel readers spoil me rq when do they get together is it like 10 chapters before the end of the novel or what..