Rosboy is a term for a feminine boy or man. Rosboys consider themself a boy or man, either from having a connection to boyhood/manhood or desiring to be outwardly perceived as boys/men, but also have a connection to femininity also can be feminine in some way, whether that be in gender or in presentation.
This could be entirely internal or external through gender expression non-conformity; some ways of expressing this are through alternate pronouns, names, physical expression, mannerisms, desired titles, etc. though these are not necessary components.
It is an umbrella term for all identities that involve being both a boy and feminine, including feminine-aligned men and men who present femininely.
The female counterpart of rosboy is azurgirl.
History
The term rosboy and the flag were created by Tumblr user Neopronouns on July 17, 2020.[1]