I did this a couple times - mainly because the lack of weight gain on my wife in a good 3-4 years.
It always starts with me by not noticing a gain in myself until one day I realize I developed a little gut, then I scratch my head and realize I have been eating a lot more in the last month or so. I took advantage of this staring point a couple times and decided to stuff myself to the max, drink Heavy cream and milkshakes after I was full with food. I became extremely aroused and focused on my belly getting bigger and bigger and wanted my wife to either tease me, scold me or even have a talk with me about how big of a gut I was packing on.
She never really commented, so I kept going hoping for a teasing or a scolding from her, but instead she started feeding me larger and larger portions as well as second and even thirds where she never used to. The good news was she was eating a lot more during this time as well and was gaining quite a bit herself. So, I kept going looking for the comments or teasing. Some 45 pounds later all mostly to my huge gut that made me look like I was 15 months pregnant I finally got some teasing while she was slightly intoxicated while we were on vacation. It was all endearing and touchy and she seemed to have a hidden desire to really love it when she was quite tipsy. When she sobered up she didn’t pay it much attention, just let me keep eating myself fatter.
I began to like fattening myself and seeing the direct effect rather than watching her gain. The secret part adds so much of a arousing desire that somehow is probably instilled in this fetish in so many ways.
1 month
