Mild Seven

Nagai's ecchi parody of Mikiya Mochizuki's Wild 7

(from ebookjapan):

The Seven Soldier Family is the world's most powerful mercenary family. We call them the "Mild 7"! Wherever they go, they have no enemies. Where the Mild 7 goes, Mild 7 kills everyone who stands in their way! Led by hippie dad Draemon, 36 years old, the Mild 7 make use of machine guns, missiles, rockets, tanks, fighter planes, and even a submarine battleship, the Yamato, which was converted from the sunken Yamato, in their basement.

This is Go Nagai's quintessential masterpiece, a messily erotic and violent work!