There is nothing wrong with either party sleeping with each other on the first date.
Sometimes these things happen simply due to circumstance and the right set of situations, to avoid it for some man made rules is pritty silly imo.
There is rules as posted but this are sociaty rules, there is also a rule that transends that and that is one of NATURE! And sometimes you cant help to let it take its course.
Now if people want to judge that is fine, I too would also prefer a women to wait for sex, but then again she may just be waiting for sex with YOU! and actually as slept with guys on meeting them for a few minutes, thus it proves nothing if she sleeps with you on the first date or not.
A far better indication of trust is how she is with you and other men, how much she is into you and how much self esteem and maturity she has. An attention who** can go many weeks without sex, but this does not make her a fitting GF, on the same scale a quality women can be sexed up with the right circumstances forming for you and for her that would not normally happen, which equals great sex.
So the rule is a stupid one not thought out and imo only people that have actually analyzed it or thought about it from there own ideals and not forced opinion can escape the riggures of basing assumptions on something that is all cases is simply NATURE.
So me personnally i would like a girl to wait as its ingrained, but in all fairness i also realize it is BS and if the right women came along and we have se* on the first meet, i would be a complete fool to let her go!
On the other hand if i was not into her anyway, i would still maybe try to get se* out of her and if she did NOT give it, i would simply not see her again, as it would be a waste of my time.
Which is catch twenty two, so to me its not about sexing and leaving on her, for a majority it is about simply guys wanting sex and nothing else, making excuses, simply due to i guranteee if the right women knocked on any guys door here and offered sex after a great date, none would dump her or if he did i would brand him a fool!
Its a nice ideal but it simply does not work and if it is a bases of your method, i would advice you give it a second thought, especcially if you meet a women who is so into you due to a connection, with that amplified through the right situations and circumstances led to sex, then no dumping her is not wise imo.
On the other hand if you meet a girl who syas she simply wants coc* then yes you have what some would consider a slu*, but then again it is doubtful she wants a relationship from YOU anway.
Also women enjoy sex shock horror, face it they do and some women actually persue something they enjoy so what? It is a pleasure and women enjoy it, so branding women slu* for seeking something out they enjoy is not really looking at the full picture, granted some do it other reasons, but there is no dispute WOMEN LOVE SEX, if you dont think so, then hey no sweat of my nose.
What is left then if you date her or not and i know 100% most guys AFC ofc would stick with a slu* who offers it to him, simply due to him not getting it from anywhere else as well as other factors!
Slu*s get BF too, trust me on this and the poor bastar*ds are none the wiser since a true slut women is a master at this game and will play you, so the sleeping thing, you may just have been played, whilst shes fuc*ing your best mate e.t.c So this rule can come back and bite you on the as*.