I've done this before, it didn't work out because it was her first time. She became too occupied about questioning reality and feeling 'tasty'. I'd ask her a question and she'd say "how do I even know you're real"- NOT useful when trying to get somewhere relationship wise brother, trust. Oh yeah and don't make any major moves because if she regrets it afterwards you'll get accused of trying to take advantage while she was under the influence. Once she knows her psychedelic experience better then yes, definitely.