I feel it's definitely got the capability of fluid retention. I practice 'tubing'. When removing the tube, I sometimes retain bit of fluid behind the glans. Removing it is slow and high-pressure, which ends up pushing that fluid into the glans in a VERY noticeable but even bubble (much like what a burn bubble looks like, with the extremely smooth-looking skin). This is also where Lipen is placed, in Dr. Cho's glans-enhancements (directly over what is called the lamina propria and under the outer epithelial layer).