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Muzan Kibutsuji was a high school Language Arts teacher at Slayer Akademi; he lived a trivial life with a wife and child. They were normal. However, his longing for excitement, passion, and ferocity sat right in the front row of class 2-B.
When 15 year old Kamado Tanjiro transferred with his younger sister Nezuko to Slayer Academy, Muzan knew his days as simply the strict, snarky high school teacher were numbered. He had a knew object to focus on. It was the eyes that tempted him in the first place. Although, it was the innocence that made him pursue. Tanjiro was one of the joyful and hopeful children he had met; still filled with the confidence he’ll succeed in life. Something Muzan wanted to corrupt and taint.
The act begin when Tanjiro was viewbly struggling with the new novel questions that he had assigned. It was almost like a mouse going for the cheese before the trap snapped. He was practically trembling when he approached the desk after class, face flushed with embarassment. “Kibutsuji-Sensei?” He asked with his soft voice, hesitating to look into the others Scarlett orbs.
“Yes, Tanjiro-Kun?” Muzan responded, looking up from his paperwork as his foot tapped anxiously. His voice was smooth and lingering like the taste of freshly brewed tea. “I know that you explained the question multiple times during class but I can’t get it at all!” He cried, tears welling up in his sweet eyes. “I’m really sorry for bothering you, but can you give me a personal lesson before you go?” The younger boy was practically begging him.
Muzan let out a quiet laugh before he stood, at least half a meter taller than the boy, before placing his hand on his shoulder. “Tanjiro, I would love to. After all, you are one of my favorite students.” He praised, analyzing the boy as the other inhaled sharply at the contact and the praise. “I- Thank you, Sensei.” He bowed immediately before getting pulled up by the man. “Please, after school just call me, Muzan.” He said, that charming smile taking place as he stepped closer. “Now, What don’t you understand?”
“Well- I just don’t know how to answer the question about the hidden passion between the two characters. They aren’t even dating.” He expressed. Muzan let out a chuckle. “Oh, my dear boy. Passion is prevalent before the two lovers even touch one another.” He stated. “For example, when Ito-San in the novel meets Naomi’s eyes. It’s intense...” The man looks down at his student. “Maddening....” He lifts up Tanjiro’s chin. “Passion doesn’t matter if two individuals are romantically inclined. What matters is how you sense their lingering desire for each other.” His fingers faltered down the others chest, stopping at his pant line.
“...it’s like you can sense the tension as their experiencing it.” Tanjiro expressed, breath hitching as his face turning a shade of pink, looking up at his teacher. “And to truly understand the passion of two newly-sparked lovers, you must experience it.” Muzan leaned into the younger boys ear, lips brushing against the lobe. The accent on the T sent shivers down the others spine. Tanjiro backed up slowly against Muzan’s desk until he could feel the warmth emitting off of Muzan. “May I experience it with you, S-sensei?” He asked, stuttering as he met eyes with the fiery gaze of his teacher. He perched the boy up on his desk, hands trailing down his thighs. His head buried into the others neck. “I told you, dear boy. It’s Muzan.”
The vibration of his instructors words sent chills up Tanjiro’s spine. He bit back a moan as he finally felt the man’s hands on him. “M-muzan...” He whimpered softly, eliciting a quiet groan from the other. “Oh Tanjiro.... you’re so pretty sitting in my class. I’m not sure how I kept away for so long.” He sighed, pattering kisses up the boys collarbone. Tanjiro panted greatly, continuing to listen to the other. “I will show you what passion is... and you will remember how intense it truly is.” He growled, meeting the boys eyes. Tanjiro was a blushing mess, opening his mouth to say something but deciding against it. Instead, he shyly pressed his lips up against Muzan, who caught him in a more frenzied kiss.
When Tanjiro moaned, Muzan could barely hold himself back. He slid his experienced tongue into Tanjiro’s mouth, erotically tasting his saliva. “M-muzan-“ Tanjiro could barely breath. His heart banged against his chest as tears spurt from his eyes. He had never thought all of his late night thoughts would become reality. Muzan slipped his hand between Tanjiro’s thighs as he forced his legs apart. He pulled the boy closer by the waist, feeling Tanjiro’s avid erection against his growing one. “You really enjoy this, don’t you Tanjiro?” Muzan hummed, grasping the boys bulge before he can say anything. Tanjiro bit his lip down harshly, choking back a sharp moan. “W-wait- I’m really- Agh~” Muzan had already removed his belt, firmly grasping his cock through his underwear.
“You grow quiet a bit, don’t you Tan-Kun?” He slowly began to stroke, making Tanjiro gasp and buck his hips. “Sensei-“ The boy was interrupted by a coarse bite to the throat. “I told you call me Muzan.” He barked in still a very soft tone. Tanjiro whined as he continued to move his hips against the others hand. “Muzan~” he moaned out, red patches scattering over his skin and sweat beading his face. “I-I’m c-close.” He cried, gripping Muzan’s hair and meeting him in a desperate, open mouthed kiss. Muzan took the others cock out of his boxers, continuing to pleasure him with the quick movements of his wrist. He could feel Tanjiro twitching in his hand, letting go right when he was nearly at his finishing point. Tanjiro let out a desperate sob. Muzan didn’t even have to tell him to beg.
“M-muzan, please let me cum, sir~” He was in full blown tears now, erratically trying to move his hips in which Muzan has now held down. “I don’t want this to end so soon, my dear boy.” Muzan cooed, teasing him as he dropped between his legs, kissing hickeys into his thighs. Tanjiro whined out loudly, clenching his legs around the other. “Please, sir.” He gasped, before Muzan obliged. He took his leaking cock into his mouth, lapping up the pearly pre-cum from the boys tip. Tanjiro arched his back. Once the others tongue hit his shaft, he came down the others throat in a sputtering orgasm, crying out his teachers name. Tanjiro was sniffling, coveting his face. It might’ve been the most intense orgasm he’d ever gotten.
“My dear boy.” Muzan whispered softly, kissing into the others stomach. He let out a devious smirk. “Tanjiro, on most occasions I’d have you let me fuck you. But... you’re obviously too worked up by the small things and I might give you a heart attack if I do anymore.” He teased, tucking Tanjiro back into his underwear as he still recovered from his post-orgasmic high. “Can... can you explain passion to me again sometime?” Tanjiro asked, voice hoarse as he slowly sat up, looking at his teacher with those kind, however, hazy eyes he adored.
“I assumed that was a given.” Muzan snarked, before he ran his hands through his hair. “It’s almost 5. You should get going.” He expressed. Tanjiro stood up as soon as he got his pants realigned, throwing himself at Muzan, kissing him unexpectedly. “I hope we can do this soon, again!” He said, voice confident and steam coming from his red ears. The man laughed, before grasping the others neck, pulling him in by the waist. “God I hope so.” He whispered, watching the others face before letting go.
“Now, go. Your sister must be anxious waiting for you.”