If he burned 20 seconds of Sage Mode in a real fight, the cost-benefit ratio was terrible.
But that was because his "mixing chamber" was only the size of his forearm. If he could expand the quarantine zone—maybe to his whole arm, or torso—the duration would increase.
But he wasn't Naruto. He couldn't spam it.
For now, it's not a combat mode. It's a steroid.
Aokawa realized the true value of his discovery.
Sage Chakra was regenerative. Unlike normal chakra, which drained physical stamina, Nature Energy revitalized the body.
Normally, extreme physical training (like Might Guy's) damaged cells. To recover, cells had to divide, shortening the telomeres and effectively reducing one's lifespan.
But Sage Chakra repaired the damage without forcing cell division.
Plan:
Use his massive spiritual energy to monitor his body limits.Train until muscle failure.Use the 20-second Sage Mode to flash-heal the micro-tears.Repeat.
He could train 24/7 without rest days. He could speedrun a decade of gains in a year.
It's an XP booster.
But there was a catch. Opening and closing tenketsu repeatedly was stressful on his meridians. He couldn't do it too often, or he'd cripple his own chakra network.
Slow and steady.
Gurgle.
His stomach roared, breaking his scientific reverie.
He looked out the window. Noon.
Aokawa washed up and headed to the living room, expecting his grandmother's feast.
Instead, he saw a man.
Thirty years old. Tall. Sharp features that mirrored Aokawa's own. He was sitting on the floor, methodically organizing a ninja tool pouch.
"Dad. You're back."
Hyuga Fu.
Aokawa's father. A rare survivor in a world of dead parents.
Fu was a Chunin. Or rather, he was a capable Chunin. Years ago, a mission gone wrong ended with an explosion that shredded the nerves in his right leg.
He survived, but he was crippled. He could walk with a limp, but he couldn't run.
In the ninja world, mobility was life. A ninja who couldn't run was a liability. No team wanted him.
And because of the Caged Bird Seal on his forehead, the Academy wouldn't hire him as a teacher. The Main House wouldn't allow "secrets" to be potentially exposed to non-Hyuga students, and the village administration saw the seal as a political headache in a classroom.
So, Hyuga Fu was stuck doing D-Rank and low C-Rank missions—courier jobs, farm work—scraping by on pennies.
"What were you doing in your room all morning?" Fu didn't look up, inspecting a kunai for rust.
"Just... trying out a new move," Aokawa replied vaguely. He pointed at the pouch. "Why are you packing gear? You don't need kunai for weeding missions."
"The Clan notified us. Pensions are being cut by 50% for the next six months."
Fu turned around, his face weary but determined.
"With inflation on ration pills and tools, the D-Rank pay won't cover our expenses anymore."
"I'm taking a C-Rank suppression mission. Clearing out a mountain bandit stronghold. The deadline is close."
"If I default on it, I'll be blacklisted for six months. We can't afford that."
Aokawa frowned. "Bandit suppression? That requires sweeping a mountain. With your leg..."
If the bandits run, you can't chase. If they ambush you, you can't retreat.
"Let it go, Dad. I can take missions. I can support the family now."
"You?"
Fu scoffed, a mixture of amusement and fatherly dismissiveness.
"You're a brat. You think you can feed a family?"
He stood up, wincing as he put weight on his bad leg.
"School starts in two days. Focus on mastering the Three Basic Jutsu so you don't fail graduation again. We'll talk about you working after you get your headband."
"But—"
"No buts. I'm the father. I put food on the table."
Fu slung the pouch over his shoulder, the metal clinking softly. It was the sound of a broken soldier marching back to a war he couldn't win.