Series Kigo Question

Why do people ship Kim and Shego?

Kim is a minor throughout the series, and it's well established that Shego is a full-grown adult. She is a fully accredited schoolteacher and has shown interests in other adults.

Even if Kim is 18 in the end, wouldn't this ship glamourize adults waiting for kids to turn 18?
Why does this ship get the pass?

Seriously, if Shego were a guy, everyone swooning and fawning over this ship would be foaming at the mouth if a twenty something guy were hitting on an underage girl for years.