User blog comment:B214/Volume 22 spoilers/@comment-182.58.115.129-20161117141232/@comment-10330822-20161117160421

I'm pretty sure most people suspect he's Black anyway. Crom is the romaji is read as "Kuro", meaning that Mr. Crom, would be Kuro-san. Likewise, "Kuro" also means "Black", which means it is a play on words. Mr. Black is another way of saying, Mr. Crom.