Honestly my best guess for the "fruity" thing is that Caitlin is the sort of upper middle class Londoner who has a handful of wealthy gay men in her orbit that she imagines herself as being able to sound like, but none of whom are fond enough of her to correct her when she fails at it.
Idk about that but fruity *also* used to mean horny back when
it was the sort of mild euphemism that an uptight sitcom husband might hesitantly utter when enquiring if his attractive but distant wife was open to the idea of marital relations, in something like "The Good Life" or Reggie Perrin
it's a bit coy, a bit ooh-aren't-I-naughty but she's the same age as me so she probably picked it up watching the same shows in the early 80s 🤷♂️
"fruit" and "fruity" as pejoratives for gay men are something I associate with US movies and books; the UK had different slurs at the time AFAICR
i regret to inform you that so many 20yos and younger have been using fruit and fruity for like the past five to eight years
they've also reclaimed the limp wrist flip, idk how i feel about it
Oh, and fair warning: borderline not-safe-for-work British euphemisms, just so you know. I laughed, I recoiled, and I noted that, yes, actual *competence* is refreshing. But I don’t know if I’d express that in quite this way…um. Yeah.