Since I did Naruto OG stories mixed with Boruto characters (aka Mitsuki/ Naruto and his group) but now I will base it off Shippuden (for now) with a story about Sai. Hope you enjoy!
Splatter all over! Ninja art : Secret Beast Scroll
Sai ran into the forest. Naruto and Itachi caught up to him. "Hi Sai..what's going on?" Sai coughed and jumped onto the lower tree branch. "Hi Naruto..Itachi..have you brought the rest of the group with you?" Naruto's head turned sideways. "Sai..you okay? You don't sound right." "I- *cough have a *cough disease since the last time we went to Amegakure *cough I can't seem to tell what it is..maybe it's poison from those pesky ninja *cough.." "Sai..you should rest.." "T-thank you Itachi.. *cough...maybe we should *cough continue.."
"No.." Naruto stopped and turned on his chakra mode. "I will take Itachi and leave..you stay here and rest..I'll send a medical team to get you.." "But- *cough wait!! I can be off some use! *cough...maybe Itachi can! He's edo right now but he can help me!" "Sorry Sai but you can't come with us.." "But-" "Just wait until the medics come..they'll be here shortly." Naruto's cloak glowed. "Alright. See ya.." He ran ahead. Itachi, Kakashi, and five more followed. (1- nagato, 2- obito, 3- deidara, 4- isshiki, 5- madara)
Sai took a rest near the tree. "Phew..I hope that I can recover fast.." He ate a food pill and waited. A few moments later, there was a rustle in the bushes and the medical team came out. "Sai!!" "Sakura..what are you doing here? I'm *cough okay.." "Don't worry Sai..you'll be alright..we're in still pursuit of Sasuke anyway.." "Wh-ere is he?" "Somewhere in a cave..we were told to head there after Itachi's orders were sent to retreat with Naruto's group..we just stopped here because we needed you to be alright.." Sai took out his scroll. *rustle *rustle "Uh..what's that?" "It's probably the Amegakure ninja..they have come to hunt me.." "But what about you?" "Stay back Sakura..I can handle the Amegakure ninja.." "But-" "Just go!!" "No..I'm staying.." "Fine..just stay back.."
The ninja came and cut through the bushes. The leader stood there and held out needles ready to attack. "Enough with your wimpy squeals..it's our job to kidnap him immediately..everyone charge!!" They charged straight at Sai. He dodged and sent kunai. Then he reached down and started drawing. "Ninpo: Chojyu giga!...." Sakura peeked out from the bushes. The drawings started to come to life. But they looked a little weird. The monsters were all lions and huge about the size of a human being. Their mouths held tips of bow and arrow strapped at the ends. "Hoshi Kogeki!!" The lions all shot their arrows and knocked down the ninja. Sai put away his scroll and collected the arrows back into his scroll. Sakura gasped. It wasn't anything like she saw before. It had to be a summoning of a lion archer. Orion.
Sai put away his scroll and Sakura stepped out of the shadows. "Wow Sai..that was magnificent..where did you learn how to make beast constellations?" "Well, I read it in my book that I studied of astronomy.. *smile it's a very interesting book.."
"Oh well..I hope that I could read it too someday.." "Yeah.." Just then, Naruto's group returned. His chakra mode already stopped glowing. "Hi Sakura chan and hi Sai..I see that you are alright..that's good..well, let's return home.." Naruto and the others jumped through the forest.