A/N: I haven't written in a while so...
My take on Kakashi's boggart :) I hope you enjoy this (Note: this will be a oneshot)
The boggart swept from victim to victim, a grey storm morphing into each student's worst nightmare.
From Kakashi's position in the back of the classroom, it seemed incredibly funny to see each student face their mundane fears such as teachers, spiders, scolding parents, and the likes. They all seemed so simplistic and normal compared to the horrors faced in the Shinobi world. He had faced worst situations and dire times during the course of his shinobi career and life; and yet these children seemed so afraid of their fears.
Of course, Kakashi didn't let the children notice how much he was shaking with laughter.
His laughter ceased when the boggart flew to the back and right in front of him.
Without hesitation, the boggart split into four distinct shapes, and each shape began to take form; Otousan smiled earnestly at his only son, seemed to say 'Hello son, did ypu have a good day at the academy today?'; a cheery Obito, brimming with arrogance, hand on his goggles and a sunny grin appeared, 'I'm going to beat you, Bakashi, and become the Hokage!'; Rin, hands entwined behind her back, full of kind leafy eyes and sweet smiles ('Congratulations Kakashi!) and Minato-sensei, cerulean eyes filled with pride as he gave his student a thumbs-up, 'You did good today Kakashi! Keep it up!'.
Kakashi stared, entranced by the tranquility and happiness projected by the four most important figures in his life. His mind screamed, 'No! It's a trap! It's a boggart! It's some sort of genjustsu, snap out of it!'- but his traitorous hand reached out, because he just wanted to touch them, because they meant the world to him, because he loved them and shouldn't have ever let them go, because he wanted to accept the reality that could've been if he had just-
Otousan was the first to shift.
Otousan's kind eyes glazed over as he slumped face-first onto the bloodstained flooring. Thunder boomed as the mantra 'You weren't worth living for' echoed. His knees gave away as he relived the night he came back to find his motionless father, thoughts penetrated his defenceless walls. 'No no no no, Otousan would never have just left me like that, because, because-'
'What? Because he loved you? Because he actually cared for you? If he really did, would he really commit suicide?' , A part of him fired back, 'Would he really had left you ALONE? No, you were WEAK, you couldn't do ANYTHING to stop him! He was right, because you weren't worth living for at all!'
His aching heart clenched as the image of his dead father who deemed him worthless to live for, glared back at him.
Then Obito's image flickered, causing more students to scream.
And that's when his stone-cold heart shattered as easily as glass.
Obito's body convulsed as a huge force smashed onto the right side of his being.
'You failed me, you failed her. How could you? You let me die because you weren't strong enough.'
'I died because of you. Why did I die for you? I never should've pushed you out of the way. I should've let YOU die.'
Obito's voice, full of sorrow and hate sounded wrong, because Obito was supposed to be living happily and making lame excuses and trying to impress Rin, and isn't supposed to be hateful and full of rage-
Because Kakashi, he, couldn't save Obito.
Rin's previously cheerful and happy image flashed; now she stood, tears flowing past her purple-striped cheeks, dull eyes boring into his own tear-pricked eyes, a gapping hole that was once her chest, identical to how she looked as Kakashi's Chidori pierced her. 'Why couldn't you save me? You broke your promise to Obito; I died in YOUR hands. You did this to me, you killed me; and now I will never live again.'
Kakashi couldn't breathe; he could feel the slick and thick blood on his hands and his chest felt constricted, as he took in her true words, because he did indeed murder her and took away her freedom to live.
Rin snarled, her face the picture of demonic, before she too, slumped forward.
Sensei's once-bright yellow hair was stained red; face pale and lifeless as his soul was extracted by his own jutsu.
Memories of Team Minato drowned him as they flew by; Obito's stupid and lame excuses for being late, Kakashi berating Obito for being late once again, because he never stopped being late, Rin trying to make peace between the two of them and Minato-sensei in the background, shaking his head as he took in the scene of this three beloved students.
And so he snapped.
He ignored Lupin-san's attempts to calm him, the student's cries of terror and the world around him.
He screamed for Rin, for Obito, for Sensei, for his father. He screamed for his and their futures, and what it could've been so many years ago, and how it was all his fault. Agony filled himself as once-buried grief washed over him like a menacing tsunami and drowned out the horrified cries of the student body.
Above all, he screamed because the four most important figures in his life would never forgive him.