them with a chubby partner?
Since you didn't really ask for any characters, I decided to go for my sugars :) I haven't really gotten to write for them.
Sugar: Could he sleep on top of you? Like... please?? He doesn't sleep as often as canon Sans but he does sometimes like to lay down and he would just love it if you let him sleep on top of you, it would be so comfortable! Plus, you know, why not? He isn't too heavy himself... he won't bring up your weight ever and if you want to lose weight, he'll support you but if you don't wanna? He'll still support you. He really doesn't care about your weight he thinks you're beautiful no matter what.
Sweetie: He really likes chubby people! He thinks that they're just the cutest little thing. Sometimes he'll squish your tummy while laying behind you and giggle. He enjoys making you a lot of snacks whenever you get hungry but hey, if you don't like it, he'll stop doing the squishes and feel a little bad for making you uncomfortable he just thinks that you're adorable! He can't help himself. If you really don't like him doing it though, he will. He wants you to know that he loves you no matter what you look like... you're his datemate, and he's just happy you're his.
Fireball: He loves the fact that you're chubby, he'll often watch you walk, and sometimes he would buy you clothes that show off your curves a bit more than normal. He tell you how beautiful he thinks that you are all the time, and will cuddle you and sometimes squish where his hand is, just because... squishy. Squishy is nice. If you're not happy with your weight, he won't force you to stay chubby but, you know, if you like yourself chubby but other people make you feel bad he's gonna be pretty pissed.
Spices: As long as you're healthy, he doesn't really care about your weight. He likes it when people are a healthy weight, and if you want to be chubby, then you can be and he won't force you to change or anything... As long as it's not, you know, too much and you aren't sick he loves you because you're you, not because of your body... he does like the squish.
Spooky: He is one of the biggest people that loves chubby people. He thinks seeing them with a few extra pounds is really good, and really attractive. Maybe it's because of how long they were without food? He has no idea, just he knows it makes him happy to see them full and sometimes he'll sit behind them and rub their tummy, giving it soft squishes. It, strangely enough, relaxes him! If anyone is ever mean to you about your weight, he's going to get pretty annoyed and will hold onto you protectively, growling softly at the person. He won't try to hurt them or anything but he can still be pretty scary if he needs to.
Scaries: He's the type of guy to ask you, if you ever say you want to lose weight, why? If it's just because you want to, he'll help you but if it's because of someone teasing you or you feeling bad about how you look he'll hum and make you something to eat. He thinks that you should be in your happiest skin, and you can't let someone else decide that skin for you. He likes your chub, and loves how you hold yourself. He wants you to love yourself just as much as he loves you. Or even just half as much!
Sugarburst: No matter what your weight is, he would love you! Sure, a bit of extra squish never hurts anyone but really, no matter how heavy or light you are, if he loves you he loves you. He will give you a bit of a workout by running around and you having to try to keep up but other than that? He won't force you to work out with him unless you want to! As long as you're healthy, he's happy. Expect him to buy you clothes to show off your curves though, he wants you to show off a little because of how pretty he thinks you are, everyone around you should have the pleasure of seeing you too! Though, he's the only one with the pleasure of having you as his datemate so ha!
Lolli: Just like all the others, as long as you're safe and healthy, he doesn't mind whatever weight you have. If you ever feel bad about yourself, he'll tell you that he thinks you're beautiful no matter what you look like.