It's not what you think.
Pound Cake lay on the table, babbling incoherently and smiling up at his loving father.
"Awww, who's got a messy diaper? You do!" Mr. Cake said with a warm smile.
The toddler giggled and flailed his limbs, a small line of snot running down from his nose and into his mouth.
Mrs. Cake had taken Pumpkin Cake with her on a girls-only trip, leaving Mr. Cake to care for his son alone. He didn't mind, however, as he was more than used to changing diapers and breast feeding his babies.
Mr. Cake took the diaper off, and his smile immediately dropped. Confusion hit him like a brick, followed immediately by horror. His son's penis was partially emerged from its sheath, a small pink tip visible. Mr. Cake's heart raced, and he blinked, his instincts of self-preservation quickly taking over. The wet diaper forgotten, he bolted into the kitchen and grabbed a knife in his hooves, holding it out in front of himself in a shaky defensive stance.
"Don't... don't come any closer, you hear? I have a weapon!" he called shrilly, his eyes glued to the empty doorway, expecting his attacker at any moment.
Pound Cake, still lying on the table in the other room, tilted his head in confusion. His daddy was gone. He rolled onto his belly and, using his wings to slow his descent, fluttered to the floor. He had seen his daddy go toward the kitchen, and hobbled on unsteady legs in that direction. It wasn't long before he poked his little head around the corner, seeing his father over by the counter holding a knife. Being one month old, he didn't know what these things were, and simply wanted to be with the familiar pony again.
"N-no! Stay back! I... I know how to use this!" Mr. Cake threatened, standing his ground, but quaking in terror.
Pound Cake took small steps forward, unafraid of the meaningless words. Mr. Cake's eyes widened. He quickly turned and grabbed an empty metal mixing bowl, and threw it at Pound Cake. The bowl sailed over the tiny baby, striking the wall with a loud clang, then fell to the floor. As it rolled, Pound Cake frowned, and his eyes grew tearful. He cried, wailing loudly as he stumbled forward, the presently-blurry figure of his father still recognizable as a place of safety.
Mr. Cake screamed in horror. He slashed the knife wildly, in a threatening gesture that meant nothing to his son, and the handle of the blade slipped free from his tight hoof grip. Time seemed to slow as the knife fell to the floor, clattering uselessly into a corner, and his son was upon him. Adrenaline flowed through him, but his quick and panicked motions betrayed him as he turned to grab another weapon. He slipped and fell back onto his rump, his rear legs splayed open, and his sheath and plot exposed to the room. The infant closed in on him, still crying. In a last desperate effort, he threw his forelegs up in front of his face and shouted.
"Noooooo!" he cried. But it was too late. Pound Cake reached his hind leg and clutched it with his tiny hooves, clinging tightly while he sobbed. "Get... get off of me, you filthy pervert!" Talking was no use, however, as his one-month-old son could not understand his words, and wanted only to be with the only pony he trusted.
Pound Cake, sobbing in great wails, worked his way forward, trying to climb onto his father's belly, and thus nearer the safety he needed.
Mr. Cake shivered and cried as he felt violated, his son between his legs and moving and doing Celestia-knows-what, for his eyes were tightly shut. His stallionhood slipped from his sheath and hardened, unbidden and unwelcome, and he squirmed, but he dared not resist from his position of utter helplessness.
Pound Cake continued crying, and his movements were not coordinated enough to easily climb onto his father from his position. His front half was on Mr. Cake, his back half still standing on his stubby hooves on the floor, and his wings flapped awkwardly and lacked the ability to lift him up in his panicked state. He wanted to be held, comforted, stroked by a loving hoof, and nuzzled by a familiar muzzle.
Mr. Cake cried, and through his terror, was able to control himself enough not to scream, for he knew that angering his attacker could be the last mistake he ever made. His member jumped, and between sobs, he squeaked out helpless whimpers. He swore silently he would not cum. He would not give that monster the satisfaction.
Mr. Cake's biology betrayed him.
His tip flared, and a mix of shame and pleasure overwhelmed him. What would normally be a grunt of satisfaction came as a gasp, the sound of defeat, and a seed of self-loathing and doubt in its infancy was planted deep in his mind. Physical evidence that he had enjoyed the filthy act leaked from him, matting his coat. His thoughts were an endless string of no, no, no, denial already his best hope of preserving the shredded remnants of his dignity.
Pound Cake's nose wrinkled as an odd and unpleasant aroma reached it. As Mr. Cake stretched a hind leg out, it lowered enough for Pound to climb over it, earning him slightly better proximity to his father. Still crying, after he straddled and then made it over the leg, he was soon at his daddy's side. A yellow hoof suddenly pushed him back, and he slid across the floor easily, back near Mr. Cake's hind leg. The hind leg pulled back and slammed into him with enough force to knock the wind out of him. Confused and deeply hurt in many ways, he lay in the middle of the kitchen, dazed and in pain.
Mr. Cake had seen an opportunity to get his attacker away, and took it immediately. With Pound in the middle of the large kitchen and looking temporarily out of commission, he quickly climbed to his feet and galloped as fast as he could out of Sugarcube Corner.
Nearly an hour passed.
Pound Cake had tried to follow his father, but he couldn't open the door, and ended up crying and eventually sleeping on the floor by the main entrance door.
He woke to the sound of loud bangs on the door. Then it opened, and large ponies stepped into the bakery, having to scoot Pound out of the way. The newborn began crying anew.
Mr. Cake followed the guards into his shop.
"Th-that's him," he said, pointing at Pound Cake. "That's the one who... who... r-raped me."
Two guards looked at the baby with stern gazes. They marched to him and picked him up bodily. A third, the captain of the Ponyville guard, spoke.
"Don't worry, Mr. Cake. We'll put this bastard behind bars. He will be lucky if he sees the light of day before his mane turns gray," he said.
"Thank you..." Mr. Cake whispered, looking down.
"Now, let's get you to a hospital. Everything will be okay."
Mr. Cake nodded as if to say yes, everything will be okay, and I believe you. But he wasn't so sure it would be.