Holos that have a canonically great ass:
>Aki
Approaching hag territory means she has more body fat stored, she also eats and drinks a ton of good stuff and Aki's one of the most fit holos, with experience in dancing, especially belly dancing. You just know she can fill out some tight-fitting mommy jeans real good.
>Aqua
A recluse who's gaining weight over time, but described as small and frail and takes her idol activities seriously, if you flip her skirt, you'll definitely see something real nice.
>Shion
This mesugaki has a tight booty and she knows it well, ever titillating those ojisans with a shake of her hips and those smug looks. The short short she wears are further proof of this: they accentuate her charm quite well and they beg for a firm grasp.
>Subaru
The owner of the softest ass, she's displaying a classic tomboy feature: a great body hidden behind those masculine clothings, yet her buttocks still stand out. With great hip movements and tons of energy, she's a dangerous foe.
>Okayu
Those onigiris have to go somewhere and they go to the best place: her deliciously plump rump. With the addition of her fluffy tail and her dangerously lewd behavior when she wants to, Okayu is a femme fatale for all asschads.
>Marine
The undisputed queen of asses. Countless stories and visual evidences tell a story about a magnificent ass that's begging to be touched and played with, especially knowing it's horny owner. No wonder that none of her outfits dare to downplay it.
>Rushia
The cunnyssieurs know a great, bouncy butt when they see one, and Rushia's is no exception. Thousand of fandeads are wishing across the globe to be sat on, and Rushia would gladly do that for them if she's sure of their love towards her.
>Noel
Just because she's mostly known for her magnificent tits, that doesn't mean that she doesn't have the ass to pair them with. Logically thinking, the fat in those mammaries means that she's pleasantly plump all around. In addition, she also works out so it's not all just fat, but has that much needed firmness to it.
>Towa
Towa might be an angel, but her delightfully devilish, delicious derriere desires to be drooled all over. Jean shorts are a perfect fit, and her devil tail adds a further punch with its waggling.
>Kanata
Heimins across the globe fell in love with Kanata shaking her hips and wearing nothing, but her rugged T-shirt at most times. Her ass is practically begging to turn Kanata into a fallen angel.
>Moona
Don't be deceived by all the junk food she eats, this Indonesian beauty has a supermodel's body, and with that comes a supermodel behind. Both her new outfit and her original one also pairs said behind with skintight pants, carrying a dangerous thread down below the Equator.
>Polka
The fennec fox has shown us some great, plump thighs and those thighs can't connect to something significantly worse. Just imagine her standing between you and the sun in her new sundress, and catching a glimpse of her buttocks through the opaquely see-through fabric.
>Kiara
The trash compactor that destroyed Subaru's bin, combined with her dancing experience leaves many KFP desiring to be hatched under the Kiara culo, as she has promised previously for her 3D debut. Those buttons are unbuttoned for a reason, you know?
>Ina
>just let me move my giant ass
Isn't that enough?
>Gura
The final member of the cunny trio, she refuses to wear pants at all times she can, evidently to free her butt from the constrains of them and showing it to all the world. Her shark tail props up her onesie she wears, further showcasing her ass to the world, making everyone go UUUUUUOOOOOOOOOOOOOOOOOOOOOHHHHHHHHHHH
>Sana
Beeg Sana has a beeg behind, making her the owner of the largest ass across all of Hololive, reaching celestial measurements. The leotards are also a nice touch, fitting snugly on her darker than averagely pigmented cheeks and running between them ever so slightly.
>Fauna
Mother Nature's ass is nothing but natural, as a cardio bunny, Fauna takes great pride in her efforts, and she's rewarded with firm and formly buttocks as a result. If you take two U's from her catchphrase, you can see just how round said buttocks are.
>Baelz
The final entendree of this list, the rrat has a wonderful body of a shortstack, which she barely hides with her chaotic clothes. Baelz is also quite bratty and bold, and you just want to lay her across your lap and spank her great ass when she acts up until she's putty in your hands.