Ignis and Gladio are sworn to serve Noctis – in every way. They're taught extensively on how to please a man in bed, and are groomed (from as young an age as author anon wants) to see this as part of their duty.
+ Noct doesn't even realise until his 16/18th birthday when he's told he's allowed (and expected) to use them sexually too ++ Before this Noct had the biggest crush on one or both of them (if just one preferably Ignis tho) +++ other, distant members of the Imperial family taking advantage of their rank and non/dub-conning Ignis and/or Gladio because that's still technically part of their duty
Ignis+Gladio/Noctis, groomed for Imperial use
+ Noct doesn't even realise until his 16/18th birthday when he's told he's allowed (and expected) to use them sexually too
++ Before this Noct had the biggest crush on one or both of them (if just one preferably Ignis tho)
+++ other, distant members of the Imperial family taking advantage of their rank and non/dub-conning Ignis and/or Gladio because that's still technically part of their duty