Why is it frowned upon

for someone to talk to more than one person. me personally i don't see an issue with especially if your just 18. cuz i'ma tell females man ya'll are a piece of work like a job. i remember the other day my professor ask us if we had a choice between a light skinned girl that was beautiful,intelligent and wealthy and a dark skinned girl with the same statistics which one would we pick. So she decided to ask the blackest nigga in our class to answer so he lied and said dark skinned. So then she asked another student and he said he would talk to both. Then out of nowhere the whole class went in a uproar. Mainly because 80% of the class are females so you know he had it coming. So i was thinking to myself that i would do the same thing. Now i'm not trying to sound like a player but man it's just like applying for a job you put out like 2 or 3 applications and hope that someone calls you back. And yeah sometimes we call to check the status on the job. Then finally when you get hired by one job you stop calling the other places you applied to because your now employed. It's the same thing with a female. You should talk to multiple women at one time but when you start to get serious with one you cut the rest of them off. at least thats what i do.