it's not Japanese! it's Chinese.
and 姦 is a word with bad meaning......
I can't speak for the Japanese, but considering kanji are derived from Chinese hanzi, maybe I can help out?
I'm not sure if it would have the same meaning, but usually Chinese hanzi are the same as kanji. If so, this points to a sexist ideology. It's important to remember that the characters are 2500ish years old, so views have changed, but even so, I can't say I like it.