It may not be "wrong" but it has it's own set of "issues".
Who doesn't like having sex with 21 year old TW girls?
But there MAY be some sort of price to pay.
But hey, if you "love" her (not just in a physical way) and she "loves" you, why not? Life is for living. Age is a number.
I would caution that 21 year old TW ladies may be mentally much younger and you should treat her with "kid" gloves.
Be genuine with her and be prepared to go all the way with her. And let her "dump " you instead of dumping her as their minds are gentle and she may jump off a roof.
Don't let that happen . And don't jump off a roof yourself hear? Or be pushed off .
I would say if you are free for there to be a future with her and genuinely affectionate and kind to her, why not see what happens. If she loves you back and her love is true?
Young ladies often believe strongly in Love. Be her fairy tale but not her nightmare.
TW girls will steal your heart ! Be forewarned. And they often play for keeps. So if you are not prepared for the long haul be sure to let her down easy.
Anyway some of them are tuff as nails and would end up breaking YOUR heart .