Kazuya Hiramaru picked up an issue of Jump on the metro, thought it was something he could do, and then quit his job to draw manga. He had a manga getting serialized in Jump called Otters 11 which was later cancelled. Later on he serialized the one-shot he entered into the Super Leaders' Love Fest, You Can't Reach Me. He is also a heavy drinker, but this is only shown in the party for Jump authors, which is the only time his editor isn't watching him like a hawk to make sure he does his work. Because of such, it stands to reason that this is one of the reasons why he drinks.
Hiramaru was a salary man that hated working. In the anime, upon hearing Takagi and Mashiro talking about drawing manga on the subway and finding an abandoned copy of Jump , he quit his job to be a mangaka because he thought it would be less work for him. After teaching himself to draw manga in a very short amount of time, his manga, Otters 11 is serialized. He is hailed as a genius by Yoshida who pushed for his serialization saying that Hiramaru had no real motivation to continue as a mangaka and failure would just make him quit.
Hiramaru is extremely lazy and immediately regrets getting serialized due to the amount of work to keep up a weekly series. He has said that he doesn't know why people have to work for a living and that he wants to sleep when he's tired and to eat when he's hungry. Due to his laziness, his editor, Koji Yoshida, often schemes to manipulate Hiramaru into working. Hiramaru often tries to escape Yoshida to avoid working. His attempts to escape Yoshida is a long-running gag in the manga.
He's also a chronic hypochondriac and often makes incredible claims of illness. However, he is always proven healthy by the doctors. It's mostly believed that his "illnesses" are not only a product of his own fears, but also serves as an excuse to avoid work.
He is also obsessed with women, especially young girls. One of Yoshida's schemes to get him to work is to introduce him to young pretty girls. He also has a huge crush on Aoki Yuriko. Yoshida bribes him into doing work by giving him weekly facts about Aoki. Yoshida also often depicts dramatic scenarios of Aoki rejecting him due to his laziness or inability to produce names to energize him to work hard. Because he cannot stand the idea of losing Aoki in his life, a combination of his own anxiety and Hiramaru's end-game scenarios, he works feverishly in hopes his work will earn Aoki's heart and eventually gets engaged to her in Chapter 160. [Source: wikia]
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