I read this sometime in the 90s but it may well be older. I remember
A female character had been fitted with a system that allowed her to induce physical pleasure (orgasms at will if you like) as restitution for a crime committed against her1. Part of the story arc was another character's attempt to convince her to leave her bubble of pleasure (I seem to remember her as floating for some reason) and help the main character.
The major plot twist was that at the end we realize that
the narrator is actually the main character's ship that was given sentience at some point during the novel's story. The last chapter is narrated by her (the ship) in the first person.
I really don't remember much else about it apart from that it was far future and space opera(ish). Also, sentient ships were not the norm, this is not a Banks book for example.
1 I was a teenager, that's the kind of thing that stuck in my mind at the time.