I tried looking for the video and apparently the I was wring about the scene.
The swimsuits were more ripped off by some small aquatic torpedo-like makchine that was dropped into the pool rather than dissolved.
Heres the link to the video I found:
http://www.watchanimeon.com/katte-ni...-ova-episode-2
The scene you want a gif of is the first one after the opening.