Cao Cao: He sticks his finger up his nose to pull out a booger. "Whoa! Big one!" He looks around to see Sima Yi standing near him. He flicks it onto his face. Sima Yi notices immediately and he twitches. "Ugh!" He wipes angrily and walks off in a huff.
Cao Pi: He discreetly picks his nose and when Sima Yi goes to pick up paperwork, he sticks it behind his back.
Xiahou Dun: He just does it and flicks the booger to a random peon.
Xiahou Yuan: "This is bothering me..." He picks his nose behind Xiahou Dun's back and sticks it on one of Xiahou Dun's shoulder pads.
Cao Ren: Uses the blade on his shield as a Q-tip.
Zhang Liao: When he was still with Lu Bu, he would pick his nose then stick it on one of those red "antennas" Lu Bu had on his head.
Zhang He: You never see him do it, but I bet he does.
Zhen Ji: She picks her nose VERY VERY VERY discreetly and flicks it onto Sima Yi's back as he walks by her.
Cai Wenji: She'll use a tissue.
Wang Yi: You don't see her pick her nose, but you'll see her stick the boogers onto random men.
Pang De: He digs around for a bit until he pulls a giant goopy mess. He tries to flick it, but it stays stuck. He sticks the booger on his helmet where the creature's head had its mouth. With him knowing, the helmet comes alive to eat the booger.
Li Dian: "My nose iches..." He looks around for a bit to find no one and proceeds to pick his nose. He digs for a bit, then gets a speck out. "Ok, now to get rid of it..." He walks by Sima Yi's office and greets him. "Heeeey."
"Hello." Li Dian pats Sima Yi's shoulder and says in a sing-song voice. "Looove yooou." He wipes off the booger off him.
"Wait, what?"
"Byyye!" He leaves the office, leaving Sima Yi in confusion.
"And I said Zhang He was weird..."
Yue Jin: He picks his nose and wipes his finger off of Li Dian's scarf. He later feels guilty and tells Li Dian about it.
Xu Huang: He uses a tissue.
Jia Xiu: "Nrragh... Stupid... Ah!" He pulls out a big speck out his nose and looks around. "...No one... Ah!" He spots Sima Yi and gives him a pat on the back. "Has anyone told you your hat looks stupid?"
"What?"
"Nooothiiing." Jia Xiu wipes off the booger onto Sima Yi's back and walks off.
Guo Jia: He just makes sure the ladies don't see him pick his nose. He then sees Sima Yi walk by him and he flicks the booger onto his back.
Dian Wei: He digs around his nose for a bit to pull out a large booger. "Big one! Now where can I put this...? Eh." He just sticks it on the wall.
Xu Chu: He picks his nose and then eats the booger he just pulled out.
Wu
Sun Jian: He picks his nose and flicks it off without anyone noticing.
Sun Quan: He uses a tissue.
Sun Shang Xiang: She sticks her finger up her nose and digs around to get a large booger out. She does get a scold or two from her mom, Lian Shi, and lady servants.
Zhou Yu: He doesn't want to stain his fingers nor give you the image of his pretty face doing an obscene act, so he blows his nose into a tissue.
Taishi Ci: He picks his nose like it is nobody's business. He gets out a large speck during a meeting.
Sun Ce: He sees Taishi Ci picking his nose and competes with him. "I can get a bigger one! Watch!" He pulls out a goopy mess after he sticks his finger up his nose. "Haha! Beat ya!" The two then wiped their boogers under the table without anyone seeing them.
Huang Gai: He gets rid of the boogers by flushing out his nose with water.
Zhou Tai: You just don't see him picking his nose.
Lu Su: He picks his nose to flick it somewhere off and it hits Zhou Yu in the face. Zhou Yu looks at Lu Su with a "I'm going to kill you" look. "...Lu...Su...What-"
"Bye!" Lu Su hops out of his desk and runs for the door.
Lu Meng: He uses a tissue, but may occasionally stick his boogers onto one of Gan Ning's bells if he didn't have any on him.
Gan Ning: He just picks his nose angrily and then flicks it square onto Ling Tong's face. Ling Tong notices the speck immediately and is completely disgusted. "UGH! EEEEEW! Get it off!" He turns, and hits the wall directly in a panic. He falls as Gan Ning watches him and laughs hysterically.
Ling Tong: He picks the nastiest booger he could get and flicks it onto Gan Ning as revenge.
Lu Xun: After he gets out a large speck of booger, he makes a big ball out all of his boogers and sets it on fire.
Da Qiao: Uses a tissue.
Xiao Qiao: When she is about to pick her nose, Da Qiao makes her blow her nose into the tissue she had ready for her.
Ding Feng: Uses a tissue.
Lian Shi: Tissue.
Han Dang: No one really know if he picks his nose or not.
Shu
Liu Bei: He tries not to pick his nose in public, but he's awful at hiding when does try.
Zhao Yun: The spear acts like a giant Q-tip.
Zhang Fei: He always picks his nose.
Guan Yu: You don't see him do it.
Zhuge Liang: He picks his nose, then gets rid of the evidence by shooting a laser onto the booger.
Yue Ying: Tissue.
Ma Chao: He picks his nose, then sticks it on about anywhere. Even on a horse if he's desperate.
Huang Zhong: He's old, old people pick their nose every chance they get.
Jiang Wei: Uses the spear as a Q-tip.
Wei Yan: He wears a mask, so no debris can get into his nose, thus no boogers.
Pang Tong: He wears a mask, so no boogers.
Guan Ping: He does it, and gets embarrassed when someone catches him doing it.
Xing Cai: Tissue.
Liu Shan: Just does it and sticks all of his boogers everywhere.
Ma Dai: He uses his paintbrush to pick his nose sometimes.
Guan Suo: Tissue.
Guan Xing: Tissue.
Bao Sanniang: Picks her nose and sticks the booger on random peons.
Xu Shu: Does it matter?
Zhang Bao: He pulls out a goopy mess and wipes it off Guan Xing's scarf.
Guan Yinping: She picks her nose, and flicks it off. It hits a peon, and he falls because of the force placed onto the booger.
Jin
Sima Yi: Tissue or him picking his nose and sticking the boogers onto Cao Cao's or Cao Pi's desks or any Wei desk. Sometimes on someone if he feels like it or in a certain situation.
Sima Yi looks around him for a bit and proceeds to pick his nose quickly. He looks around to find a place to stick it on and notices Sima Zhao. He walks up to him and pats his back while wiping the booger off of Zhao, "Proooud of yooou."
"Huh? Are you okay...? Why are you proud?"
"I'm fine. Now move along." Sima Yi walks far from Sima Zhao sight to give out a small snicker. "I never thought...Kmph... I would say that...Hahahaha... to him out of all people! Hahahahaha!
Sima Shi: He pulls out one of those sticks out of Sima Yi's hat and picks his nose with it like a Q-tip. He then puts it back.
Sima Zhao: He snickers at Sima Yi's "decorations" on his back and picks his own nose to flick a booger onto his back.
Zhang Chunhua: Tissue. She notices Sima Yi's "decorated" robe.
"...Kmph... No, no... that's not funny.. kind of..." She keeps some laughter in to tell Yi about what's on his back.
Wang Yuanji: Tissue. Makes Sima Zhao use a tissue when she sees him picking his nose.
Guo Huai: He sneezes a lot, so his nasal pathways are usually clear.
Zhuge Dan: Uses the rod he carries to pick his nose.
Deng Ai: The drill he carries acts like a motorized Q-tip.
Zhong Hui: You don't see him do it, but the flying swords kinda indicate what he is doing though.
Wen Yang: He picks his nose, and no one knows since he's high up for anyone to notice.
Jia Chong: He discreetly picks his nose and flicks it onto Zhong Hui's face. "AAAAAH! GET THIS OFF ME!" Jia Chong watches in amusement as Zhong Hui run around panicking about the fact his face has been tainted by a random booger.
Other
Lu Bu: When he picks his nose and flicks it off, it goes through three house walls until it hits a random civilian square in the face and falling down due to the impact.
Diao Chan: Tissue and may stick the boogers onto Dong Zhou's back back when she was still with him.
Zuo Ci: He doesn't get them. He can just make them disappear.
Dong Zhou: He's always doing it and is just going to stick his boogers in random spots.
Zhu Rong: Uses the boomerang's tips to pick her nose.
Meng Huo: He always does.
Zhang Jiao: He can just make the boogers disappear.
Yuan Shao: Uses his rapier to pick his nose, and not in public either.