It was during a fairly routine training exercise that Benmaru first acknowledged his own mortality. He was flying through the forest, whirling, dancing with twin spears in hand while sharp blades flew at him from all directions. The young cub grinned with exuberance, avoiding and ducking the onslaught as he knocked the knives harmlessly to either side.
A moment of distraction – something that moved in his peripheral vision caught his attention – and suddenly he barely had time to widen his eyes in shock as blades rushed to his heart and throat. Thoughts tumbled through his head – his long-range spears were no good, it was too close already, he'd failed His Lordship in the most ignoble way and he'd never eat dango again, when a green blur placed itself between him and oncoming death.
Benmaru's eyes focused on this new phenomenon to find his ninja-guardian standing casually with a blade balanced between each forefinger and thumb.
"Might I recommend some armour, Master?"
"Sasuke," breathed the youth in admiration, "how did you get there? You appeared as though you were a shield cast from heaven!"
The ninja chuckled a little self-consciously at the praise but said lightly, "It's sorta my job Master."
"To be my shield Sasuke?"
"If you wanna phrase it like that, I guess, yeah."
The cub raised his head and declared resolutely, "I failed in this training exercise Sasuke, but you did not. You were there, and while you are there this Benmaru has no need for earthly armour for I believe in the strength of my heavenly shield." With that, the young warrior rushed off to complete his routine.
Some time later, when the newly anointed Sanada Yukimura proudly showed off his battle garb, Sarutobi Sasuke, Head of the Sanada Ninja Corps, looking blankly at his young lord murmured, "Good grief, no need to make it easier for me then."