As many of my friends know, I am a strong fighter against casual sexual relationships. I have always believed that it was wrong.
As I have argued many time before, lust is often the most important reasons, for this, not responsibility. Time and time again, the purpose of man and woman coming together is undermined, the reason, being to weave the next ring of the web, the web of human generations.
People in these relationships are not bound by law to anything. No responsibility means that the children that are born, are illegitimate. It brings shame to both families.
So yes, definitely against, but the root of this is mainly due to casual relationships that start at teenage life. So, tbh, it is quite expected that the longer society sees bf and gf as normal, the longer this problem will persist.
Thats why you see so much of it in America, UK, Canada etc....