User blog comment:Miskos3/Fairy Tail Episode 238: Tartaros arc: Immorality and Sinners, Review/@comment-24200891-20150620152105/@comment-7418318-20150620161514

I don't consider naked torture to be ecchi.

Ecchi is something that can be enjoyed and torture definitely doesn't qualify for enjoyment... at least not for me.

In this case the nakedness was to me another layer of torture. The way I see it Kyouka tried to make Erza as exposed and helpless as possible to undermine her mental resistance against the physical torture.