Sakura sighed for what felt like the hundredth time, as she half-listened to Lady Tsunade's afternoon lesson in the newly renovated operating theatre set up within the Hokage's residence.
"Oh, would you quit moping already, Sakura?" Tsunade snapped. "All that sighing is starting to depress me!"
Ignoring Tsunade's warning, Sakura sighed again— prompting her sensei to whack her on the back of the head.
As if Naruto leaving for two years wasn't enough, now Sasuke was going away too… Kakashi had asked the Hokage for permission to take Sasuke on a long-term training trip, and for some reason Sakura couldn't begin to fathom, Tsunade had accepted.
'At least we still have our girlfriends,' said Inner Sakura cheerfully. 'Lady Tsunade might be a demanding teacher, and things might still be a bit awkward with Ino, and Karin might still be an unrepentant stalker, but with Naruto out of the way, we can hang out with them all we want!'
"Now listen here, you," Tsunade said sternly. "You're the one who kept complaining it wasn't fair being the only one on your team without a summon— so the least you could do is pay attention while I'm trying to teach you how to get one!"
Kakashi-sensei had his ninja hounds, Naruto had his ninja toads, Sasuke had his ninja cats… Sakura was the only one who was still summonless!
"I thought we were talking about making me your official disciple," said Sakura, startled. "Besides, didn't we already do the whole disciple ceremony thing with Tenten, Ino and Karin-chan?"
"That's one thing, and this is another," said Tsunade as she massaged her temples, sensing a headache coming. "I agreed to teach all of you Medical Ninjutsu and the Healing Arts because I wanted the village to have more medics, but haven't you noticed you're the only one I taught my special techniques to? That's because I'm making you my official disciple— and learning to summon slugs is part of that."
Even though Tenten had been the first of the Konoha 12's young kunoichi to request a spot as her disciple, Tsunade had known from almost the very beginning that Sakura would inherit her legacy. Sakura was the most compatible with her skill set— and, most importantly, she was a hard worker and a quick learner.
"Moving things right along," said Tsunade as she took a scroll out of her coat pocket, "before anything else, I'll have to test your compatibility with Space-Time Ninjutsu— if it's zero, we'll have to give up."
Tsunade unfurled the scroll and spread it out on an operating table.
"No need for hand signs," she explained. "Just smear a bit of your blood on the paper and run your chakra through the Jutsu Formula inscribed on the parchment."
"Do I really have to do this?" asked Sakura, tapping the scroll pouch strapped to her thigh. "I can summon my sword from anywhere using its summoning scroll, remember?"
Tsunade scowled.
"I'm aware," she said irritably. "Just do as you're told, okay?"
Completely puzzled, Sakura flipped a senbon into her palm and pricked the tip of her index finger, drawing a droplet of blood. She then smeared the crimson liquid on the white paper, extracted a bit of chakra, and sent it out into the Jutsu Formula until it was filled.
Poof!
Thick white smoke erupted from the paper, completely obscuring Sakura's vision. But rather than dissipating after a few seconds, it persisted… though the smoke suddenly seemed to grow much colder, stuffier and damper.
"What did you have me summon, Lady Tsunade?" Sakura coughed, waving her arms to clear away the smoke. "The inside of a chimney!?"
No answer came.
"…Lady Tsunade?" Sakura repeated after a few seconds. "Are you still there? Is this your idea of a prank? Because it's not very funny…?"
Sakura wandered forwards blindly, arms stretched out in front of her to avoid bumping into anything. If she just happened to stumble into Lady Tsunade and accidentally grab her plush breasts... well, she'd only have herself to blame, wouldn't she?
Eventually, Sakura's hands touched something smooth, soft and moist— and also very slimy.
"Kyaah!" came a girlish scream.
"Did you take a shower, Lady Tsunade?" asked Sakura uncertainly, groping the soft mass. "You're awfully wet… ah."
The smoke swirled as something massive stirred in the distance.
With a slight shift from the mountainous figure, rays of afternoon sunlight pierced through the veil of smoke. Light filtered through the cover of leaves overhead, and as the air warmed, the smoke began to lift— revealing that Sakura was no longer in the Hokage's residence, but in the middle of a dense jungle!
'That wasn't Jutsu smoke!' exclaimed Inner Sakura. 'It was fog!'
"Eep!" cried a stagecoach-sized blue and white slug as Sakura let go of its posterior.
Sakura bounded up the nearest tree, gasping as her head broke through the canopy. It was as if an impressionist painter had taken a brush to the ordinarily blue sky, adding to it all sorts of unreal colours such as yellow, orange, pink and green.
"What in the—"
Despite its strange tinge, the sky was far from the most impressive thing in sight.
Even across the vast sea of leaves separating it from her, its sheer size made it hard to judge just how far and how big it truly was. Standing tall at 12 000 metres of height, a blue and white slug towered over Shikkotsu Forest below…
"Is that Lady Katsuyu?" Sakura whispered in awe. "She's bigger than Fuji-san!"
Several netizens have already estimated the God Tree's height to be around 20 000 metres, assuming the Shinobi Planet to be roughly the same size as Earth. These calculations are typically based on either the planet's curvature or the average altitude at which clouds form.
In the original timeline, Sakura and Tsunade combined managed to summon 10% of Katsuyu's true size, and that incarnation of the slug was around the diameter of one of the God Tree's roots. Using maths and a ruler, we can estimate 100% size Katsuyu to be under two thirds of the God Tree's full height, so 12 000 metres is a fair assumption to make.