A quick note on tagging: You can't tell from the image alone, but the person out of frame is Himura Nagisa. In the script for this card's story, Nagisa mentions that she can't see Kanade's "beautiful skin" under her jacket and asks Kanade to excuse her, with Kanade audibly reacting immediately after. This CG is displayed during these lines, which indicates that Nagisa is pulling Kanade's jacket off.
I originially tagged this as 1girl + 1other because I didn't think that was sufficient evidence at the time under "tag what you see," but the discussion in forum #28923 leads me to believe tagging it this way is acceptable as long as there is enough evidence overall to support it.