Yamato actually has an identity in Konoha, Danzo Shimura helped Yamato get ninja status, Yamato is a legitimate Konoha ninja, not undocumented.
The danger Danzo Shimura referred to was not that Yamato would encounter danger, but rather that Yamato exposing his identity as a Wood Release Ninja and being taken away by Sarutobi Hiruzen would pose a danger to the Root division.
"There should be no problem with the right plan in place." After careful consideration, Danzo Shimura decided to bring Yamato into Konoha.
After repeatedly testing, Danzo Shimura could confirm that Mokgetsu was extremely loyal to him.
With loyal Mokgetsu around and combined with his Root forces, it was actually very difficult for Yamato to be discovered.
Danzo Shimura was a man of strong action. After confirming his thoughts, he dispatched his most trusted subordinate the next day to bring Yamato into Konoha, then called Mokgetsu to the Root Base that evening.
"Lord Danzo," Mokgetsu greeted with a face full of respect.
Mokgetsu had a hard time guessing what Danzo Shimura wanted from him before arriving at the Root Base this time.
Because he already had an important task that occupied most of his time and had no time for other matters.
However, after using Byakugan to scan the entire Root Base before arriving, Mokgetsu had a slight guess, but wasn't very certain.
Seeing that expression of respect that had remained unchanged for decades, Danzo Shimura was quite satisfied.
"I have a very important mission for you, which concerns the future of Konoha!" Danzo Shimura said in a deep voice.
Yamato, as the second Wood Release Ninja after Senju Hashirama, was considered by Danzo Shimura to be as important as the Tailed Beasts.
"I'm willing to give anything for Konoha's future," Mokgetsu said without hesitation.
"I will immediately have a Shadow Clone apply to the Third Hokage to cancel the training mission."
With that, Mokgetsu formed hand signs and created a Shadow Clone, which immediately rushed towards the door, seemingly eager to dash towards the Hokage Building.
Danzo Shimura's eyelids twitched suddenly. If Mokgetsu suddenly told Sarutobi Hiruzen he wasn't doing the mission anymore, given Sarutobi Hiruzen's attention to Mokgetsu, such an abnormal event would definitely lead to an investigation. If anything were really found out then, it would be bad; Root couldn't afford such scrutiny.
"Mokgetsu, dispel the Shadow Clone first, listen to me, don't be too hasty," Danzo Shimura hurriedly stopped him.
Just while he was thinking, the Shadow Clone had already run out of the office, and he worried if he didn't say something soon, the Shadow Clone would sprint towards the Hokage Building.
Mokgetsu's actions were too vigorous, to the point of extremism.
"Lord Danzo, didn't you have a mission related to Konoha's future for me? If I don't end this training mission, I won't have time to accomplish your task," Mokgetsu asked puzzledly while dispelling the Shadow Clone.
Danzo Shimura felt a little strange now. Although what Mokgetsu did was unfavorable for him, he felt immensely gratified in his heart.
"He was even willing to find Hiruzen to end the mission just from hearing a single sentence from me."
Danzo Shimura thought Mokgetsu's every move now exuded loyalty.
"Ahem," Danzo Shimura cleared his throat lightly, explaining, "Although this task is very important, at this stage, it doesn't require too much of your time; you can proceed with the training mission as usual."
Mokgetsu showed a suddenly enlightened expression, then quietly stood still.
"Your task this time is to teach the Wood Release Ninjas of the Root," Danzo Shimura no longer played the riddle game and stated the specific task.
Mokgetsu looked at Danzo Shimura with a face full of shock, as if hearing something unbelievable.
Danzo Shimura couldn't help but show a satisfied smile; no Konoha ninja would be unsurprised to hear such news.
"You are the best ninja I've trained since the establishment of Root, and I believe you have the ability to shoulder the responsibility of instructing the Wood Release Ninjas," Danzo Shimura said looking approvingly.
Danzo Shimura thought that Mokgetsu's loyalty to him should be at its peak at this moment, given that he was entrusted with even a significant figure like a Wood Release Ninja.
Mokgetsu cooperated by displaying a grateful expression, thinking to himself that Danzo Shimura really had a unique boldness. From Danzo Shimura's perspective, his current strength should be credited to Sarutobi Hiruzen, but Danzo Shimura still calmly said such words without a blush or heartbeat.
Then Danzo Shimura walked out of the office to the adjoining room to bring Yamato to the office.
"This is the one you will instruct next, his codename is 'A'," Danzo Shimura introduced.
In Danzo Shimura's place, Yamato did not have a name, only a codename.
Partly because Danzo Shimura really did not know Yamato's name, but more so because Danzo Shimura wanted Yamato to treat Root as his everything through this method, to take the Root codename as his name.
Otherwise, couldn't Danzo Shimura just easily assign him a name?
"He is the Habu Mokgetsu I mentioned to you before, the most perfect ninja in Root," Danzo Shimura said looking at Yamato.
He once told Yamato some of Mokgetsu's exploits, encouraging Yamato to strive to surpass Mokgetsu.
Yamato raised his head in confusion to look at Mokgetsu, who also turned to look at Yamato with a slight smile.
"So bright."
Yamato only felt that Mokgetsu's smile, like morning sunlight, and his golden hair made the dim office seem much brighter.
That bright, warm feeling made Yamato inadvertently develop a fondness for Mokgetsu, even if it was their first day meeting.
Sadly, though, this light soon moved away from Yamato, as Danzo Shimura immediately had Root Ninja take him to the side room again.