I literally cried this episode. Jesus christ. I have never cried for an anime in... god, a long a time. Not even Gurren Lagann. Just... wow.

13:30 - far shot of satsuki hanging in the cage
13:34 - shot of satsuki’s feet, ragged and hanging, Ragyo laughing. Panning up to Satsuki’s face until 13:43, without pausing to stare at her boobs like so many other animes
13:43 - close-up of Satsuki’s face (look of rage at 13:53)
13:54 - Looking at Ragyo talking to Satsuki
13:58 - medium-far shot of Satsuki, her body is darkened rather than well-lit. Ragyo gloating
14:11 - beginning of bad touch scene. The lighting of Ragyo is bright, the lighting on Satsuki is dark, guiding the eye to Ragyo, not Satsuki.
14:21 - Four second butt shot
14:25 - Close-up of a look of rage on Satsuki’s face
14:29 - Close-up of Ragyo’s face. Gloating.
14:36 - shot panning downwards from above Satuki’s face to her face. Seven seconds. No cleavage.
14:43 to 15:39 - Backstory.
15:40 - Far panning shot of cage.
15:56 - Butt slap.
15:57 - Shot of Ragyo and Satsuki’s face. This time, the lighting is on Satsuki.
16:03 - Closeup of Satsuki’s face into a close-up of Ragyo’s face. Still enraged / still gloating
16:09 - Shot of Satsuki’s legs from halfway down her thighs and panning downwards.
16:17 - Backwards shot of a bad touch sweeping down from Satsuki’s chest down to her behind.
16:28 - From Satsuki’s face into Ragyo’s face.
16:36 - Butt slap.
16:37 - Far shot of cage. Dark. More butt slaps and Ragyo emphasizing how much she wants Satsuki to hate her.
16:40 - Close up of faces. Butt slaps continue.
16:44 - Satsuki’s face, still mad. Still slapping. Maniacal laughter from Ragyo.
16:51 - End of the scene.

Let's recap -
lots of exposition
no lingering on boobs
lighting that deliberately de-emphasized Satsuki's body
lots of focus on the faces
fostering Satsuki's anger made a part of the conversation deliberately

If you think they spent a bunch of time on Satsuki's body you were paying attention to the wrong ♥♥♥♥♥♥♥ thing and you're using disgust to justify voyeurism. The scene wasn't fanservice. ♥♥♥♥♥♥♥♥.