If you've read the books, this should come as no surprise.
Voldemort is born as a result of a woman raping a man.
Snape's worst memory is of being sexually assaulted by a fellow male student.
Ron Weasley is the victim of a misdirected date rape drug (aimed at Harry) by a teenage girl.
Dolores Umbridge is implied to have been raped, and this is treated as a joke and something she deserved.
The mentioned "Japanese golfer joke" in Chamber of Secrets is a highly racist rape joke involving the assault of a sex worker*.
If you're thinking "Nina, don't you always say fiction and reality are two different things?," you're correct! The reason I bring this up is because when there's a pattern to the positive/negative connotations someone imparts in their writing, it can tell you a lot about their personal thoughts and biases (not always, but a decent chunk of the time). What we have here is a ten-year pattern of characters being raped and sexually assaulted and those assaults being justified, treated as jokes, or both; in the case of Tom Riddle Sr., it's even implied that we should sympathize with his rapist.
There is no case in the books of someone being raped or sexually assaulted and this being treated as a terrible thing, or even presented without comment because the audience is trusted to recognize it as a terrible thing. She doesn't even have the excuse of them being children's books because there are multiple instances of rape and sexual assault! They're just all treated as funny!
None of this, by the way, touches on the Weasley twins selling date-rape drugs or the implications of the only gay character being a headmaster who isolates and grooms young boys for his own ends.
The fact that Rowling thinks sexual harassment and assault are acceptable and funny has been apparent since at least 1999. She only has a problem with it when she's the victim.
*if you've never heard it, I apologize so much for what I'm about to say. Don't shoot me for being a messenger: a businessman goes to Japan to make a big sale for his company. The first day of talks goes well, and, elated, the businessman decides to buy some company for the evening. They return to his hotel room and make passionate love, the man's Japanese companion screaming over and over in apparent ecstasy. Thrilled at this demonstration of his prowess, the man sleeps soundly, ready for another day of business in the morning. In the morning his Japanese counterpart suggests a round of golf, to which the man agrees. He hits a hole in one, and, thinking he'll impress his opposite with his quick mastery of local culture, jubilantly shouts the same phrase he heard his paid partner use the night before. The other businessman narrows his eyes. "What do you mean," he says, "'wrong hole'?"
