I do think Jordan meant it to be funny. In the time he was writing it, it was a thing writers did, the rape that wasn't-really-rape-but-actually-it-was thing...but usually with female characters instead of male. Doesn't make it any less creepy.
And yeah, it's a different culture. It doesn't...
If we define rape simply as penetration without consent, then probably Tylin didn't rape Mat.
So I suppose technically it was sexual assault, as Eala brings up. Whatever you want to call it, it wasn't consensual adult activities going on.
I'm on the side of it being rape.
It's been a while since I've read this book, but from what I remember, Tylin keeps Mat hostage to be her sex toy. She ties him up, starves him, doesn't let him leave the palace (or has him followed if he does? Can't remember.).
I don't think it's possible to...