A black actress playing Hermione Granger? J.K. Rowling has no problem with that.

The best-selling author of the "Harry Potter" books has responded to mixed reactions after the cast for "Harry Potter and the Cursed Child" — a new London play featuring Harry as an adult — was announced Monday. The role of Hermione, made famous in the film versions by Emma Watson, will be played by Swaziland-born actress Noma Dumezweni.

Rowling said on Twitter that the character's skin color had in fact never been specified in the books. "Canon: brown eyes, frizzy hair and very clever. White skin was never specified. Rowling loves black Hermione," she wrote, adding a kissing emoji at the end.

The play, based on a new story by Rowling and others, opens July 30.