Hinata's 20th birthday causes a lot of festivity amongst the Konoha Thirteen. Since she's now able to drink, the gang throws Hinata a birthday party at their favorite bar. Things go awry as Hinata confesses that she wishes Naruto would walk her home after the party but he doesn't end up being the man to walk her to her door. Actually, she doesn't come home at all. M for allusions.
Everyone knew his life was one of loss. Everyone from his parents to his closest friends had been taken by the hands of death. So when Minato asks him to guard over pregnant Kushina, he does it as he would any other Anbu mission. Without question, attachments, or feelings. And most certainly, unnoticed. Fluff between Kakashi and the Uzumaki family. Mostly follows canon.