Sasha silently stalks towards a home. The tigress has been accepted as Santa Paws' replacement, and her quadrupedal form has already become something of an icon of the holiday season.
With each home, she appears from the shadows, gifts held gently in her maw or pulled on a little sleigh pulled by a rope when there's a lot of them. Her deceptive lockpicking skills grant her access to the property, and since time works differently for a being of holiday cheer, she can take all the time she needs.
For this home, however, she has no gifts. There are two children here who have been very naughty.
She enters the house in silence, slinking into the hall. The stairs creak under her weight as she climbs up and turns one last corner into the children's bedroom.
GRRRRWWWWWLLLLL
Her stomach grumbles hungrily as she eyes her victims.  Two little possums sleep in separate beds, a little girl and a little boy, both approaching their 8th birthdays.
The little girl awakens first, and she sits up in bed. She has cute little pink earrings that she insists she wear to bed and pink polka dot pajamas. "Huh? Is that..."
Sasha approaches the little girl's bedside with a feline smile. Without hesitation, she reaches her forepaws forward and wraps them around the little girl before pulling her into her maw. 
SLK ULP
Moving her paws down her body and pulling her in deeper, she quickly gulps her down as she begins to cry out. "B-Brober! Brober help me! Mommy! Daddy!" she cries, but her screams are muffled in the gift-giver's mouth. Her brother turns over in bed, beginning to wake, but nobody comes to her aid.
GULP ULLRP SLRRRP
Sasha finishes off the girl by slurping down her rat-like tail, forcing her down into her belly.
GRRRGGLE GLORP
While her stomach gets to work on the first trouble-maker, she moves to the other bed, where the little boy is still tossing and turning in his blue pajamas, not quite awake. One powerful paw brings the boy and his blankets out of bed onto the ground.
"Ow! What're y-"
Sasha spreads her hind legs wide and places her forepaws on the mattress. She cuts off the little boy by rubbing her cunt all over his little face. "Rrrgh..." she begins to make quiet pleasured noises as she grinds on him.
GRRRRGGG CHUUUURN GLRRRRGGGLE
The small, struggling bulge in her belly pushes helplessly against the little boy, who can do nothing about the massive cat using him as her new toy. The tigress continues to hump him more and more until his entire head slides into her pussy.
SLRRK
"Auurrghhhh... Hufff..." Sasha humps harder, gripping tightly as she pulls up and loosening as she goes down to work the naughty child into her pussy.
FLRSKRRSKK SKLLK SQUELSCHK
In a few minutes, the boy has disappeared entirely, forming a second squirming bulge drooping down from the tiger's abdomen like a hammock.
GLLRRRGGGG GLRRP PFFFFFRRRRRRT
The struggles from the first child die down as the tiger passes gas, only making the second struggle harder. As the little girl's mulched up remains begin to pass through her intestines, Sasha takes advantage of the desperate boy's fighting to pleasure herself even more.
The tigress props her back up against the side of the bed and pushes down on the squirming mass with both paws. She can't reach her pussy herself over it, but the boy pleases her fine.
GLRG GLORP GRRRRGGGGLE PFFFFFFRRRRRRRRRR...
Another passing of gas after several minutes of unconventional masturbation alerts Sasha to her need to poop. She promptly gets up and clambers onto the first child's bed before squatting down and releasing.
FBLRRLRBFGHLLRLLLBRLRBLRTLTBLRTT
A slurry of liquid cat shit sprays out onto the bed, along with a steady stream of more solid logs and small bones.
SPLATRLRLTLRBLTLRT
The child's pelvis lands in the mess, followed shortly by every one of her vertebrae, which land one by one in the pile with a small splat each. Two tainted metal earrings stained in brown shit tumble out with the slurry.
FBLRRFBLRLLRRT GRUNT... SPLRUCH PFFFFRRRRRBLRBLRLBLLRRT SPLAT
A final slew of cat shit lands in the bed before finally Sasha reaches the child's skull, which with a little effort is shoved out with substantial force, releasing the remaining gas inside of the tiger with it. As the tigress lets out a meaty, wet fart and the last few slimy nuggets of shit, the skull splashes into the pile before tumbling down the bed and landing on the floor at the foot of it, staining the carpet brown with what foul fluids it brought with it.
The big cat lets out a contented sigh, hopping off the bed and taking a pillow with her, which she places on the floor and rubs her ass on to wipe herself clean. As she does so, she takes note of the remaining child in her womb, who is squirming more violently than she's felt a kid squirm in a very, very long time, undoubtedly in a panic after hearing Sasha pass his sister.
Sasha makes her way to the little boy's bed. She keeps her feet planted on the floor and reaches up over the corner of it with her front legs before finally pressing her clitoris up against the edge of the bedframe. She begins to hump the bed furiously, grinding the little boy between her and it as she does.
SLAM WHAP SLAP SQURRRGGG
The tigress violently fucks the little boy's bed with tremendous force as her womb breaks him down into ejaculate fluid. As the tiger gets closer and closer to orgasm, he loses form entirely.
WHAM SLAP SLAM GLRRP
Finally, she reaches her climax, and the fluid that was once a small child gushes out of her pussy. The flow is powerful, and it begins to soak the floor and the boy's blankets. Countless little bones tumble out in the stream, smacking against the bed and landing on the floor and displaced bedding.
FLRRBSHLBRLTPRRR THUNK SPLAT CRACK
Every last one of the little bones flows out of her as the tigress ejaculates, one after another. A balled-up mound of blue fabric that used to be his pajamas comes out with them. Finally, his skull pops out and lands in the heap between Sasha's legs.
FBLRRRSHHHRLLRR POP FSSHHHH THUD
The tigress lets out a content sigh as the flow finally ends. Most of the room is soaked in her fluids by now, but with no time limit, she's in no hurry to leave.
She pushes some of the bones together into a pile to lay on top of and covers it with the ruined pajamas. It's not terribly comfortable, and it's rather unpleasantly wet, but it's deeply satisfying to the tiger. She rolls the boy's soaked skull back and forth like a ball of yarn.
KNOCK KNOCK KNOCK CREEEEEAAAAK
Sasha's playtime is cut short as the door to the room creaks open and the children's father peers into the room. He's a chubby possum wearing nothing but his underwear and pants that he hadn't even zipped as he went to investigate the source of the noise.
The tigress can tell the man is lost for words, and that there's nothing he can do. It's not like he's going to fight a tiger, and his kids have already been thoroughly sloshed up inside of her. 
Sasha bats the skull towards him then gets up and lumbers in his direction. She beams a big, feline smile at him. As she passes the skull, she places a paw on it and crushes it into tiny shards of bone then keeps walking.
Sasha butts past the man, who has no way to resist, and casually leaves the home behind. That's one home off the list, only a few million more to go.
Perhaps the tigress should feel bad about mulching up two children, but it's her job to deliver jolly festive justice, and they were both on the naughty list. At least, she's pretty sure; she only checked it once.