Forsaken Ninja's Self Saving System.
I will be honest, I almost went feral. The rush of serotonin this just gave me left me lightheaded. Also, I petition for Hatake Sakumo to win OroYuan's hand in marriage. I know SY is canonically oblivious to his orientation but I feel that he shouldn't be /as/ dense. Like, a smidgen quicker at realizing that he likes the guy.
But to counter the fact that he's not in a stallion novel, he's still massively distracted by all his new kids. This sick 20-something, who has likely never interacted for long with babies, now has, like, 20 of them and he's expected to experiment on them.
And on that note, he's desperately trying to figure out a way to rat out Danzo without marking himself for death. Well, more than a Sanin that everyone on the other side would really like to kill off and can be conveniently blamed if OroYuan ends up dead.
If this is during the war, after he's already experimenting, that means Nawaki already died (ps, Oro was his jounin sensei, so extra whump for the Sanins) so Oro was already looking into ways to bring Nawaki back. Maybe he remembers more about Edo Tensei so he can bring Nawaki back sooner so Tsunade comes back. Unless you want OroYuan to decide not to play God. Or make it a System Task since that was one of Oro's life goals, beyond getting his parents back from the Reincarnation cycle.
Maybe he sends a message to Jiraiya telling him to pack up his Ame kids (Konan, Nagato and Yahiko, the OG Akatsuki) and get his ass back to Konoha. Or maybe he tells Kushina that Jiraiya found an Uzumaki and isn't bringing him back to Konoha. That'll fix That problem.
Anyways, for Sakumo. He's pack minded. All those little puppies he can enjoy. OroYuan may have snakes he can summon to babysit, but snakes vs wolves/dogs? (I can't remember which Sakumo had) Scaly vs fluffy? Sakumo is the favorite. Plus, Sakumo's summons are happier puppy sitting than OroYuan's snakes are to watch the hatchlings. Also, I really ship OroSakumo. OroYuan's main hangup in this (beyond having to accept he's at least bi 🙄) is he's a single father of 20. Sakumo thinks this is fine. He's a dying clan anyway, new blood welcomed. (Same for Oro) Anyways, OroYuan is very pretty and tries his best with his new orphanage (that can be the cover story OroYuan is rolling with).
Also, I really want him to set things up to fuck over Danzo and Sarutobi. I know Oro wanted the Hat but OroYuan is like, Dictator with 20 kids and having to do research to help improve Konoha? Hahaha, no. Minato can keep the Hat. In fact, OroYuan is /invested/ in keeping Minato in power. After all, Minato purged (to an extent) Danzo's ROOT program. OroYuan just has to point out a few hidden bases here and there. Plus making sure Minato knows about whatever Danzo's using to keep his agents quiet. I forget if it's the tongue seal at this point. (An argument was made that Oro also had a seal put on him and that was part of why he went crazy, since it wasn't perfect and Oro was already mentally and emotionally unstable after losing his parents as a toddler, his jounin sensei losing trust in his humanity (that no one nurtured), his best friend runs off during the war and vanishes, his genin all die in the war, Tsunade leaving him after he let (couldn't save) her brother die, being overlooked by his sensei for the Hat when he's been the only one of his team who stayed for Jiraiya's student, and the civilians (and some other ninjas) are scared of his looks so he's always isolated) Anyways, his time at Konoha is not fun. But Sakumo takes care of all of his teammates, which is what was used to kick off the 3rd War. So he would be accepting of Oro/OroYuan.
If OroYuan wants to improve everything (if the System let's him) he could do "recon" and find out that there's a captured Uchiha and Konoha should rescue them ASAP. If Obito is in the Mountains Graveyard, I believe that it's close enough to Konoha to make them worried so twice as likely to actually do something. Hopefully, that can derail Tobi. But that's for future OroYuan to worry about.
Right now, Minato and his generation are probably chunin or thereabouts. So OroYuan can't even count on Minato to take over yet. Maybe he can install Sakumo as the Yondaime. After all, he was in the running before Danzo sabotaged him and he killed himself. So OroYuan still ends up as a dictators husband. Just one that is actually like by his people and probably doesn't blow off his work so much.
Shen Yuan quickly learns and masters Kage Bushin No Jutsu - one caretaker for every wailing baby, naturally. Oh and a clone to help him wash all that long silky black hair so that it remains silky.
(No, you don't want to know how much conditioner and shampoo he goes through every month to wash out all that baby drool.)
And well, this is a ninja village who does notice Orochimaru's increase in shampoo and conditioner purchases... and they spy on his baby supply shopping spree.
The ninja-moms quickly rope Orochimaru into their mother association meetings. Some people even come up to Orochimaru, un solicitated, to give him well intended baby care advise.
As Shen Yuan is already extremely overwhelmed about babies... he's very grateful for all this unsolicited advice because he's starting from like. Step -100.
Ninja-babies are HARD to take care of, okay? He has to deal with baby chakra monsters and bloodlines popping out at inopportune times. Especially when one baby start throwing tantrums and sobbing like the world is ending, a chain reaction begins and now Shen Yuan has a whole orchestra of screaming babies to handle.
And with chakra comes a whole new set of autoimmune disorders (related to chakra) that Shen Yuan gets to explore and learn about. First hand. Yippee /s
He's also busy trying to figure out more about Orochimaru's backstory since he didn't read that much of Naruto. And, like, this is the prequel and stuff. So many strange faces and unknown names floating around that he doesn't recognize as being in canon timeline.
Plus all the experiments he's running. He's got a lot of ideas of trying to recreate a lot of modern medicine techniques and technology into this world.
Anyways, this is to say that Shen Yuan is very appreciative of the support he's getting from the village and it shows... so people are now less nervous about going up to the snake sanin. This does wonders for Orochimaru's reputation in the village.
It also uh... starts a Orochimaru fangroup.
Anyways, with 20 kids on his hands and being an introvert surrounded by just too many fucking people day in and day out, Shen Yuan isn't going to be hunting down Jiraiya anytime soon.
Out of sight, out of mind, and Shen Yuan doesn't like perverts around him. Or influencing his kids.
Baby minds are much too malleable and can learn bad habits early on after all.
He doesn't mind Jiraiya's kid hanging around though. Minato makes a great assistant, fetching groceries and putting in orders for more baby supplies.
And then there's the really nice ninja who keeps bringing his large dogs over to cuddle the babies.
For all that Shen Yuan feels overwhelmed, he feels quite supported by the group of people he has around them. They are even helping him with naming the babies!
(Just wait for him to realize that those large dogs are, in fact, wolves. Oh and both Minato and Sukumo have crushes on him. But that's not happening any time soon.)
[More in the #shen yuan transmigrates into orochimaru's body and the naruto universe instead au]