You have the unique opportunity to do something that was never done before! A WEIGHT GAIN TIME LAPSE VIDEO!
There are some time lapse videos for pregnancies, a few for growing hair, but there is no time lapse video of gaining from thin to absolutely huge. There are some who document their wight gain, but not with a time lapse. Some only start to like weight gain and start documenting it when they are already quite large.
You have the unique advantage that you started out very thin. Don't miss the opportunity
You could create a masterpiece, a video which was never attempted before! The only thing you need is to just make one single photo every day in the exactly same pose. Preferably no directly from the front or the side, but somewhere in-between. To make it even more interesting, you can wear the same clothes for every photo, and only change for a different one when they will no longer fit.