Gaining

I'm including a feeder/ feedee pair in my book, but I want the numbers to be realist. If she started at 14, just around puberty starting, with at the time a very limited caloric intake, and the man has money to feed her, what is the most she could gain in a 3.5 year range? Would having her jump from 52.2 kg to 132kg in that time feasible? Most of what I found online only talked about muscle gain. Assume any and all gainer tricks are used, including butter or other fats. I don't go into too much detail about the gain at this point, but I would like the numbers correct as possible. Thanks!

That's easily enough time to get that fat, especially in a fictional context. Say she gained 20kg in the first year, as many young people do (e.g. my female friend, who isn't a feedee but was on exchange to America). Even if she only kept up that rate she'd have gained 70kg after 3.5 years. You only need ~80kg in total, and people who start overeating find it much easier in the long run after they stretch their stomachs out. You're well within the realms of possibility with your numbers, don't worry.

She would need to gain about a pound a week to meet that weight. I've personally done 1.5 a week for a year without a feeder so that is well within the realm of possibilities.

From my own experience, a pound a week average, for 3.5 years, is very realistic. I hate it when stories have unrealistic gains.

I don't know the context or plot, obviously, so I don't know if this is info is given to the reader to establish a background for the character who is now an adult or if it centers around the 3.5 years. If it's background info, an average works. If the story takes place during the 3.5 years, well, life is rarely that linear and things happen. Even if being deliberately fed, they may gain less than the average sometimes and more than the average other times - unless they are a captive being force fed or something. If they are just living normal life, then they may get sick, have a stressful year at school, had to take a more active class like dance or gym, maybe they travel, maybe they go on a cruise, maybe something happens and they focus on the feeding a little less for a period... Or set a goal and really focus on it. Maybe the feeder gets distracted with a new job or a family member who's injured or sick and needs extra care.... All kinds of possibilities that could average out to a pound a week.

I must say, the fact your character is starting at 14 already has my curiosity peeked - if we are following the character through the 3.5 years. Pretty much every story has all adult characters but my own interest in this topic started around 11 or 12, that I can remember. Many others on here have stated they discovered this long before adulthood. It'd be refreshing to read a good story reflecting that reality as well.

Have fun writing! :-)

They are fantasy stories and realism isn't required.

I disagree. I don't like stories that are not realistic. I hate it when someone's clothes change size automatically, or they gain 20 pounds in one day, etc.

Quite right, but the OP in this case wanted realism for their story. :-)

I don't enjoy unrealistic stories either, but there are others who do, and that's okay too. We've got room for both! :-)

To come back to the original question:
It depends on the Setting. If she is just overeating at her own pace, a gain of more than 10 kg/year is unlikely, although I have heard rumours of 20 kg/year as well. But everyone is different. If you consider stuffing, force feeding and other helps about 40 kg/year is still a realistic gain. I would not consider Money a main Limitation as a lot of fattening Food is comparatively cheap!

I'll agree that if you aren't trying to gain more than 10kg/year probably isn't likely, but assuming you're intentionally overeating then It is possible to gain some significant amounts. I can personally claim 35kg in a year through large fast food meals several days a week. I'd probably be even bigger if I'd had a feeder.