红玫瑰像大姨妈一样红
[hóng méi guī xiàng dà yí mā yī yàng hóng]
This online name uses a very colloquial and somewhat crude analogy. It's comparing the redness of a rose to menstrual blood, expressing how red it is, maybe used by someone who aims to grab attention in an unconventional way or has unique sense of humor.