After Kushina painstakingly redrew the Reverse Four Symbols Seal in the Hokage's office and explained the underlying mechanics to the Third, he finally accepted that the forbidden technique was a complete success.
The master and disciple were showered with high praise. Hagoromo, a mere graduate of the Academy, was officially labeled a "genius" by the Third Hokage.
Of course, in the Shinobi world, "genius" is a somewhat depreciated title.
With the delivery of the seal to the village, the S-rank development mission was officially closed. Kushina no longer had to rack her brain over it, and any further testing or practical refinement was now someone else's problem.
On the bright side: money. They were entitled to the hefty rewards of an S-rank mission.
Since the technique was classified as a forbidden art, it was immediately sealed away. Only a handful of ninjas would ever know of its existence; 99% of Konoha would likely never hear the name "Reverse Four Symbols Seal" in their entire lives.
Hagoromo didn't care what the Hokage did with the scroll. If you asked who the most knowledgeable person regarding that seal was, it was undoubtedly Kushina, the primary Uzumaki developer. If you asked who the second most knowledgeable person was? It was Hagoromo.
The Hokage likely assumed Hagoromo couldn't memorize such a complex formula, but in truth, it was etched perfectly into his mind. He could use it whenever necessary—assuming, for a moment, that we ignore his currently mediocre chakra reserves.
User Profile Update: Hagoromo's Mission Data
Name: Kamishiraishi Hagoromo
Age: 11
Rank: Genin
ID Number: 009887
Mission Record: * D-rank: 9
C-rank: 2
B-rank: 0
A-rank: 0
S-rank: 1
Setting Kakashi aside, Hagoromo is likely the first in his class to complete an S-rank mission. Sure, it had nothing to do with combat, infiltration, or sabotage, but a forbidden technique development is still high-risk work. He might have reached success by clinging to his teacher's metaphorical pant legs, but on paper, he's an S-rank achiever.
As for the low-level tasks, he's done very few. 20% of the reason is that he has no interest in them; the remaining 120% is that Kushina has no interest in leading a child through D-rank chores.
Regarding his internal stats (Hagoromo's self-assessment):
Ninjutsu (Nin): 8
Taijutsu (Tai): 7
Genjutsu (Gen): 2
Intelligence (Wis): 10
Strength (Pow): 5
Speed (Spd): 8
Stamina (Sta): 7
Hand Seals (Sea): 9
Total: 56 (Proper High-Jonin tier stats).
Note: A "10" in his world can mean two things: you're top-tier, or you've hit the absolute MAX.
While he has learned a vast library of jutsus from Kushina, his "Nin" stays at an 8 because he believes only a few are truly viable for frequent combat; the rest are situational or excess fluff.
But learning never stops. And that's exactly why Kushina is currently nursing a headache.
In three months, she has taught him everything she can—including ultra-high-level sealing techniques. The only things left are things she can't teach or things he can't learn.
For example: Reaper Death Seal (Shiki Fūjin). Hagoromo could learn it, but Kushina won't teach it. Handing a "suicide move" to a rookie is a recipe for disaster. If he used it out of curiosity and hung himself out to dry, who would be responsible?
Another example: Adamantine Sealing Chains (Kongō Fūsa). It's practical, powerful, and versatile. Kushina would teach it, but Hagoromo cannot learn it. It's an Uzumaki hidden technique that requires their specific chakra to manifest.
Kushina's nightmare has come true: her student's learning speed has outpaced her syllabus. She has nothing left to give.
If Hagoromo were tactful, he'd "descend the mountain" like a Shaolin monk to find his own path. But he isn't; he remains a bottomless pit for knowledge. For someone like him, knowledge is like drinking poison to quench thirst—you just want more.
(Wait, is the protagonist turning into Orochimaru? No, definitely not.)
Kushina's House
Hagoromo was busy in the kitchen like a professional housewife. Kushina was slumped over a low table, her legs lazily stretched out, chin resting on the wood, staring blankly out at the courtyard.
She wasn't daydreaming. She was thinking. (Trust me.)
Expecting the current Kushina to cook is impossible. Even after she marries Minato... well, her culinary skills don't exactly win awards. It's better to rely on the "virtuous" Hagoromo. Once she tasted his cooking—which isn't five-star, but compared to her own...—she officially retired from the kitchen.
What was she thinking about?
The S-rank mission was over, and she was bored out of her mind.
What on earth was she supposed to teach Hagoromo next?
"I've got it!"
Hagoromo had just placed the food on the table when Kushina slammed her hand down, nearly sending the dishes flying.
"Uh, Kushina-sensei, you've got what exactly?"
Kushina's eyes sparkled. "Hagoromo, my student, I'm very satisfied with your attitude and your progress. As your teacher, I've taught you everything I can..."
Hagoromo froze. Wait, is this the 'you are expelled' speech?
Fortunately, she continued, but her words didn't bring Hagoromo any joy. In fact, he almost wished she had expelled him.
"Hagoromo, I know a place. A place with a miraculous scroll that records a massive number of ultra-powerful ninjutsu. Tell me... are you interested?"