My past gf liked how big my thighs were and noted that I was starting to get a belly (this was when my metabolism was starting to slip, so I couldn't just eat whatever).
My current gf prefers me fat and we both want the other to gain so we've enabled eachother. I didn't intend to get fat but her cooking and baking (as well as grabbing my belly in sex and calling me her fat piggy) have made me happy to gain more. She also keeps squeezing my butt and thighs so I guess she likes how bottom heavy I am. Right now I'm 117kgs (1.78m) and she's 96kgs (1.6m). I'm happy to gain more but I may call it at 130kgs (if I can).
As for how we met, it was with tinder as that's the only way a sperg who doesn't know how to talk to strangers can meet girls. Just be honest and at least you'll have a chance of meeting the right girl. It may take a while but if it's to happen at all it must be done with sincerity.