"Okama" (or "o-kama") is Japanese slang for "gay man", particularly in reference to very effeminate gays. The word can also mean "drag queen."
It comes from the Edo-period slang for "anus" (using the word "kettle" for the butt seems to be an idea borrowed from the Portuguese.)
It is not always considered insulting, and drag performers will sometimes even use it in reference to themselves.
"Okage", the burnt rice that sometimes sticks to the bottom of a cooking pot, is sometimes used to refer to women like to hang out with gay or effeminate men.
Ryoji goes by the name "Ranka" when performing at the okama bar.