Eh, Fourth Wing was pretty mild. The later books are more explicit in the wording, intentionally avoiding the use of "dirty words" and instead choosing a prosaic description of events.

And tbf the entire Empyrean series is pretty mid overall. Up until the second part of Iron Flame it was super predictable and downright boring, formulaic, with a nothingburger story.

Quicksilver is much better, and the spice is much spicier. Oh and boy does it get better with Brimstone.