Yesterday I posted how fun it is to break the established rules in Regency England. But sneaking around behind a chaperone's back and a same-sex or ménage relationship are totally different issues.
The first will get you married off. The second will get you killed.
Every 'traditional' Regency book you read has some sort of rule breaking going on. Why? Because it's fun, it happened, and it makes for damn good drama.
In Ann Herendeen's interview she talks about bi-and homosexuality in Regency England.