Briana (a.k.a. Tank) convinces her friend and coworker Sandy to go with her to the beach, both as a means to boost Sandy's confidence in her own body, as well as using it as an opportunity to spend time with her friend outside of work. Sandy herself doesn't seem too keen on being out and about on the beach though, especially after she gets outside and realizes just how much she "fills out" her own swimwear.
Oh well, hopefully Briana will be able to convince Sandy to stick around and have some fun in the sun (since you know, Sandy does look pretty good in that one-piece of hers and it'd be a shame to have such a nice beach outing go to waste). X3
Oh and on a sidenote, despite Briana's interest in helping Sandy get healthy (or at least healthy-ish, as eluded to here ---> ( link )), Briana's more concerned about helping Sandy get comfortable in her own skin than anything else. This is because Briana subscribes to the idea that one should exercise and eat healthy, not so that they can become "beautiful", but rather, so they can improve themselves as people.
In other words, Briana believes that it's okay to be "plush-sized", as long as you're still striving to make good choices and making it a point to better yourself, both in the mind and the body (sort-of like trying to achieve a form of enlightenment, if that makes any sense).