Ninja Papa

Nobuo Matsuri, heir to the Matsuri Shinobi clan, was raised as a living weapon, an instrument of death who lived and breathed the art of the blade...until the day he fell in love. Now, years later, he's an unattractive thirty-something salaryman, married with kids, bullied at work, and general all-around screw up. Even worse, his old clan regularly still sending assassins to kill him for forsaking the old ways - and his family for leading him astray. Luckily, he still has his ninja skills, and ninjutsu is the art of deception!

(Source: Jmanga)