Rape is one of the most reprehensible crimes one can commit in modern society. Many people even place it as a worse crime than murder.
Homicide is a part of life in wuxia. Generally, however, "good" characters might kill their enemies in fair combat, but don't commit acts of murder. Murderers usually pay with their lives for their crimes in wuxia.
When it comes to rape, however, there seems to be a very different and disturbing message.
Consider a few infamous rapists in Jin Yong's stories:
1. Wan Chung Hok (DGSD)
2. Wan Tze Ping (ROCH)
3 Yeung Siu (HSDS)
4. Wai Siu Bo (DOMD)
Some might wonder where Au Yeung Hak (LOCH) is on this list. He was a lecher, but I'm not sure he ever actually raped anyone. He had a twisted principle about never forcing the unwilling, which would (by definition) preclude rape.
Of the four rapists listed above, only one (Wan Tze Ping of ROCH) was punished for his crime. Ironically, Wan Tze Ping was the only one of the four who really felt remorseful about his crime and repented.
I don't know what Wan Chung Hok's final fate in DGSD was, but I think he and Deun Yin Hing were the only two Great Evils to make it out of DGSD alive. If that's the case, Wan Chung Hok likely continued his life of despoiling maidens long after the narrative of DSGD wrapped up.
Yeung Siu raped Gei Hiu Fu; apparently, because she decided after the fact that she was in love with him after all, all was forgiven (it would never fly in the real world).
Wai Siu Bo: need we say more? He was like Yeung Siu x 7 (and without the virtues that might have helped save Yeung's reputation). And yet, he's the "heroic" protagonist of DOMD.
Now to be fair, not all rapists are male (although most of them are): Dao Bak Fung of DGSD might also fall under the description of "rapist" for how she took advantage of a Deun Yin Hing who was at the lowest, most desperate ebb of his life.
One can imagine things were at least as bad in the Gu Long world, although I think that ironically, Gu Long did a better job than Jin Yong did in depicting characters guilty of rape being punished for their crime (can't think of a specific example offhand, though).