Hinata by Naruto (NOT as punishment!) I'm a huge NaruHina fan and I think a picture of Naruto with Hinata over his knee, giving Her a good bare bottom spanking just for the fun of it would be wonderful!
Makoto/Lita/Sailor Jupiter - I think all of the Sailor Soldiers are incredibly spankable, but Jupiter is my favorite (She's also the only one I haven't seen getting spanked!)

Su made a few pics of Mako-chan getting spanked i believe. and someone (possibly Su again) had her dishing it out, as well! she was always my fave... TALENT!

Okay, here are a few that I can think of off the top of my head:

Inuyasha, Kagome, Sango, Miroku... pretty much all the main characters from Inuyasha...

All the digimon kids

Zidane and Dagger (FF9)

Carmelita fox and Sly Cooper (Sly Cooper series)

Tails, Amy, Tikal, Rouge (Sonic The Hedgehog Series)

Almost all the female characters from Fire Emblem: Path of Radiance... along with a few males like Soren and Rolf.

I think that's about it for right now... I know there are more, and I'll probably post them later, hehe... hope that you all like the list I have right now, XD.

While posting in another thread, I thought of one other...

Leon in Star Ocean: The Second Story

I may not have to state a reason, especially if anyone else has played the game, but that's part of the fun of it. I was annoyed with him throughout much of the game, only to regret not recruiting him permenantly. He grew on me, but darn it, that kid was obnoxious.

Leon...well, he's just asking for it.

I think Imari (Spiral Alive) could probably use one too, after seeing more of that series. D: She's very lively, and that's wonderful, but she's incredibly selfish at times too.

inuyasha koga and miroku by sesshoumaru or naraku
ed by scar
kenshin by his teacher and sano by kenshin
ryuichi yuki and shuichi by tohma
yusuke by kurama or hiei
that's all i can think of right now

Mail Order Ninja
 

AMERICAN-MADE MANGA TIME! XD I have this silly OEL series called 'Mail Order Ninja' (about a little boy who orders his own ninja out of a comic book) and there are quite a few sp-ables in there, so here's my list from it. Google at will~! XD

Timmy McAllister, 'cuz he's cute and terrorizes his little sister all the time, not to mention that he made his ninja attack people, even if they are bullies...

Romulus and Remus Wolfe - They're always arguing and stealing stuff from people (the latter is stopped after Timmy's ninja threw them into a bush). Cuteness factors in here too. :3

...and that's all I can think of at the moment. :3 :D

Pretty much every female character in YUGIOH and GX, Teen Titans, X-Men Evo and The DCAU if they all count

someone should do kairi or namine from kingom hearts being spanked.

the NUMBER ONE anime spankables are

Naruto: Naruto
FMA: Edward, Alphonse
Pokemon: ash
Megamen: lan
Beyblade:: tyson, max

I think about things like this waaaaay too much.

Let's go by anime/game (since most games i play are anime style)

Suzumiya Haruhi No Yuutsu:
Haruhi (general brattiness)
Tsuruya (see above)
Mikuru (its just cute)
Emiri (see above)

Naruto:
Sakura (both versions)
Hinata (both versions)
Tsunade
Shizune
Ino (both versions)

Bleach
Hinamori (by Rangiku or Aizen)
Rukia (by Ichigo)
Soifon (by Yoruichi)
Yachiru (by Zaraki)

Ikkitousen
Ryoumo
Kanu Unchou
Hakufu (many more times)
Ryuubi
Chouhi

Mahoromatic
Mahoro
Minawa
Sakura

Slayers
Lina
Amelia
Sylphiel

Xenosaga
KOS-MOS
T-ELOS
Shion

Love Hina
Motoko
Naru
Shinobu
Kitsune
Kanako
Kaolla Su

Rozen Maiden
Suiseiseki
Souseiseki
Suigintou

Sailormoon
Ami
Mokoto
Rei
Usagi
Haruka
Michiru
Tomoe

Soul Calibur
Tira
Cassandra
Hualin
Lynette
Valeria
Amy
Talim

Rogue Galaxy
Kisala
Lilika

I know I'm missing so many more, but I can't think of them. TT__TT