Ok I am very surpised I didn't see Erza from Fairy Tail on this list... most of the time she acts like a badass but has a super soft side that you get peaks at and at one point she mentions that some of the cute things she like restrict movement and I think she would fall on the AB side for wanting lack of control because she has to be so uptight a lot around the outside world.
This one is more of a stretch but Lelouch from Code Geass I feel like he would want to be taken care of, because of what happened to him as a child wanting to return to that innocent time for a while and I think CC would get in on it too.

It is in a cartoon, but I do believe Princess Bubblegum from Adventure Time would be a closet AB/DL (or at least incontinent)... She must be stressed maintaining the land of Ooo, and may want to relax once in a while by putting a diaper and relieving herself into it... Marceline from the same cartoon may be implied too, since she's PB's ex-girlfriend (it was confirmed by Pendleton Ward!), and may have tried and liked it... That's my 2¢ on that. -Marcy

Well it is not mentioned in the (short) anime of Disgaea, but in Disgaea: Hour of Darkness/Afternoon of Darkness there is that embarrassing photo Etna takes of Laharl that Flonne calls "cute" we never get to see the image, but after Laharl truly becomes the overlord one of King Krichevskoy's old vassals say this.

http://s28.postimg.org/siil3t37x/snap059.png

(Sorry I saved it after talking to him the first time so it will not repeat the whole conversation, but if you want to see it in game for yourself just talk to that guy in chapter/episodes 7.)

Anyways on a side note for those of us who know Laharl and how he denies just about anything from love to trusting Sicily is his little sister and loving her, but Laharl does not deny it most like because this guy has seen the photo.

(I know of a few more who maybe AB/DL, but they are all 100% from games without an anime counterpart.)

Star Butterfly ^o^, I could tottaly see her being a little with just how she acts all the time.

For me? Pan from Dragonball GT. She still sleeps with a night light, and she always wears baggy pants. To hide a diaper, possibly?

I'd say from RWBY that definitely Ruby Rose. Maybe Weiss Schnee. One can dream right.