Crossovers that Should Be: The Write Stuff

[Mamorien]

I can't be the first person to have thought of this possible crossover. And I've double-checked that the kanji used to write the names match.

Everybody calls her "Osaka", but her given name (in western order) is Ayumu Kasuga. She's never introduced her friends at school to her parents... because her parents are Kyōsuke and Madoka (nee Ayukawa).

Azumanga Daioh / Kimagure Orange Road

I figured her for a cousin, not a daughter, but I can confirm you're not the first to make that connection. (I once asked Chris Davies to confirm or deny such a relationship in the Together-verse, but only got an acknowledgement that it was possible.) The original KOR manga launched in 1984 according to Wikipedia, so I guess "daughter" is not impossible.