Ninja Papa is a manga by Yasuhito Yamamoto about a salaryman who is also a ninja.
Nobuo Matsuri is a typical salaryman. A fat, balding man of thirty-two, he works a low-paying dead end job in the customer service department of Bataph Foods. His boss is an incompetent fool who treats him like dirt, there's a thirty-five year mortgage on his home, and his nagging mother-in-law never misses an opportunity to point out his failings.
But Nobuo is happy with his life; he has a lovely wife and two kids who don't hate him. For Nobuo has a dark secret; he was raised in the Nakuru ninja clan and trained to become their top assassin. When he met his wife Aya for the first time, Nobuo knew love and abandoned the clan ways. So his former clan sends out hunters to kill Nobuo. Even worse, every so often Nobuo will run into someone who can't be reasoned or negotiated with, they threaten mortal danger to those he cares about, and he's forced to break out his ninja skills and become the merciless assassin of his youth.
As of 2012, the first three volumes of "Ninja Papa" are legally available in English on the Jmanga.com site.
Tropes that appear in Ninja Papa include:
- Acrofatic: Nobuo is amazingly fast and agile for his bulk.
- Arranged Marriage: Nobuo was originally engaged to Musashi by the clan leader.
- Ax-Crazy: Several characters, but most especially Musashi.
- Bad Boss: The new General Manager (the Manager's boss)makes the Manager look like a half-decent person, and is homicidal when confronted.
- Beware the Nice Ones: Nobuo really believes in trying to solve problems with reason and negotiation. But when the chips are down, he's deadly.
- Bumbling Dad: Nobuo is sometimes perceived as this, even by himself, as he never had a role model of a loving parent.
- Conservation of Ninjutsu: If this chapter's ninja attack in a pack, Nobuo will take care of them in a couple of pages. If only one shows up, they're a serious threat that will take a full chapter or more to deal with.
- Crouching Moron, Hidden Badass: More than one of Nobuo's opponents is taken off-guard by trying to reconcile his ninja garb with his bumbling civilian persona.
- Enfant Terrible: Musashi was quite capable of whipping a man to death at age six.
- Evil Teacher: Umi's second-grade teacher, who seems just callous at first, but has some very repellent ideas on the proper treatment of children.
- Extreme Doormat: Nobuo's normal persona. Not all that different in its way from the emotionless ninja who instantly obeys any command from the clan that he was raised to be.
- Freudian Excuse: Umi's second-grade teacher was sexually abused by his mother, which explains some of his issues.
- Good People Have Good Sex: Nobuo and Aya have an active, healthy sex life.
- Japanese Delinquents: A gang of these causes trouble in Nobuo's neighborhood and he's drafted to deal with it. He's visibly struggling to hold back and not kill them.
- Mugging the Monster: Sexually harassing Musashi, seemingly harmless school girl, is often fatal.
- Ninja: Both Nobuo and his old clanmates.
- Office Lady: Noguchi, the one co-worker who understands Nobuo's inner nobility (but not his inner assassin.)
- Papa Wolf: Threaten Nobuo's children or wife and you will not live to regret it.
- Pointy-Haired Boss: Nobuo's manager, who's sexist, racist, lazy and fails to understand the "customer service" part of "customer service department". He's abusive to his subordinates and a lickspittle to his superiors.
- Salaryman: Nobuo's day job.
- Screw the Rules, I Have Money!: Mr. Kamijo, who can have a man-eating lion attack one of his party guests for fun, and claims that he has enough money to cover up anything.
- The Stoic: The desired state for Nakuru clan members.
- Training from Hell / The Spartan Way: How the Nakuru clan raises their children.
- Ugly Guy, Hot Wife: Nobuo's wife Aya is extremely attractive in-universe and people are constantly amazed at Nobuo's luck.
- Woman Scorned: Musashi takes Nobuo's marrying Aya instead of her very personally.
- You Need to Get Laid: The Manager's advice for dealing with personal problems, always misguided.