It was no secret that Umino Iruka was one of the prettiest people in Konoha. Maybe it was his hair, and the way it made people want to pull it loose so they could run their fingers through it. Or maybe it was his soft skin, so delicate looking for a ninja's (his scars, rather than making him look tough, only seemed to emphasize this). It may have been his large, expressive eyes and the way they darkened or lightened depending on his emotions. Or maybe it was something else entirely, but whatever the reason, Umino Iruka attracted attention wherever he went.
Not just female attention either. In fact, the vast majority of Iruka's admirers were male. (This was because Iruka was so pretty, women usually considered him a rival, not a potential partner. After all, it would be very disheartening for any woman to be considered less feminine and appealing than her own boyfriend.) Rarely did a day go by in which some man didn't: 1) Comment on his good looks (thus earning a cute blush and a shy thanks), or 2) Ask him on a date (thus earning a polite refusal). This never failed to bewilder the poor sensei, because he honestly had no idea how cute he was. In fact, he considered himself to be simply…plain. He wasn't a woman and thus hadn't been taught to be dissatisfied with plainness, so this didn't bother him in the least. In fact, Iruka would have been happy to be even plainer, if that would result in him getting less attention.
It wasn't that he was a cold or stuck-up person. On the contrary, he was very sweet and kind (which unfortunately only made him seem more approachable to his fans). It was just that he had spent so much time becoming a strong ninja and a good teacher that it peeved him a little to be thought of as a pretty face first and a protector of Konohagakure second.
Besides, he already had someone in his life.
Hatake Kakashi had his own share of admirers. In fact, he had almost as many as Iruka; however all of his were female. Kakashi radiated strength in his every movement and action. There were few women in Konoha who hadn't at one time or another imagined themselves being held in his powerful arms. The fact that almost no one had ever seen his whole face wasn't a deterrent to his fans; they had it on good authority that he was handsome under his mask. (This was thanks to one of his talkative former lovers, who had also spread rumors of his superiority in other areas as well.) Basically, Kakashi was probably the most eligible bachelor in Konohagakure.
Not that his female fans hadn't tried to change that fact. Not even having his nose constantly stuck in a book of porn women from suggesting places they could go (and things they could do). Unfortunately for these aggressive hopefuls, their suggestions always ended up being politely shot down. Kakashi was renowned for his apparent high standards, having turned down everyone for the past four years. If it weren't known that his previous partners were all female, people might have begun to speculate that he was gay (he was in fact someone who didn't care about gender when it came to matters of attraction and love). As it was, most people began to think that he was a bit standoffish, and not interested in love. This theory suited Kakashi fine, because it meant people left him alone.
It wasn't like Kakashi was some sort of antisocial loner. He had friends; he had students; he had people he cared about and would die for. It was only concerning matters of the heart in which he sought to be left alone.
Because Kakashi already had someone in his life.
Kakashi and Iruka were beyond discreet about their relationship. They were out and out keeping their relationship secret from everyone (not an easy thing to do in a ninja village). Homosexuality wasn't forbidden or even frowned upon in the Land of Fire, but that wasn't the reason anyway. The official reason was that Kakashi didn't want his enemies to find out he had someone special in his life and use that knowledge against him. (And Kakashi certainly did have his share of enemies as he was such a powerful Jounin.) He certainly didn't consider Iruka to be weak; heck the man taught the next generation. It was just that he wanted to err on the side of caution when it came to his sweet Chunin. Anyway, that was only the excuse he and Iruka used. The real reason was that the two of them loved their sweet secret. They loved knowing they belonged to each other exclusively, with no one trying to separate them. For that reason, both of them were willing to put up with a little unwanted attention from their admirers. They were forever and truly in love.
Besides, it would be a sad day for both the male and female populations of the village when their secret finally did come out!