Talk:Recollections/@comment-28195974-20160518173921/@comment-177.42.255.72-20160603182337

I'm very late to the party, but not even the JP players are too sure about O-Sayo, since that prefix in names was usually used in female names like "O-Kiku" or "O-Ume" in the Sengoku and Edo periods. From what I could gather, some say it was a trend ("it sounds cute") that spread from nobles to common folk, others say it was meant to show endearment and/or respect. One hypothesis goes that the o- was to differentiate said names from ordinary nouns, since commoners had no surname and female names were often just words like "snow" or "flower".

I recall reading it isn't necessarily female and can be just an endearing way to call him, but yeah tl;dr no one knows for sure.