God Emperor has a lot of super cringey stuff in it. This is, imo, the worst. In addition to being cringey, it is maybe some of the worst writing I have ever seen.
Basically, Duncan Idaho is climbing this like 3km tall wall for reasons that I won't get into while Nayla (who is one of Leto II's weird mutant fanatical female bodyguards/soldiers who he orders to have sex with his enemies/allies for political reasons) gets progressively hornier, saying things like "[if Duncan climbs that wall] I think I'll have an orgasm". This goes on for a whole chapter. Like 30+ pages of this iirc. Then Duncan finishes climbing the wall and Hugo and Nebula award winning author Frank Herbert ends this weird horny fanfic of a chapter with "And then Nayla had her orgasm". The whole thing is ridiculously gratuitous, serves almost no purpose, and drags on in a book that already seriously needed to be edited.
A bit shit? Mate I had many long painful arguments about the quality of God Emperor back in the day on Usenet, alt.something.something.dune, The lengths people went to defend it made me realise it’s not just a bit shit, it’s a lot shit, but maybe, deliberately so.