Someone with a full gas tank.

Every day for lunch they drinks and energy drink and eat a whole bag of chip typically bbq or salt and vinegar it is most always a girl who thinks she is attractive but looks like my moms old tampon

A fat person if a person who is obese. A fat person may be slightly overweight. Do not confuse a fat person with a sedentary person.

Fat person (rephrased with broad word choice)
"gluttonous unsightly figure of great mass"

Most people, especially the self-conscious collective, will view fat people in an ill and disgusted manner, though this is irrational.
Fat people are important to society, while some are hard working people who just glutton or geniuses who reward themselves by indulging, the so-called "useless" ones greatly augment the food industry.
Indeed they may appear visually displeasing , but keep in mind that when a person is fat, the person will keep eating, increasing the food industry. For those especially industrial-fodder people trying to lose weight using dietary pills(which do not work), they are supplying two industries constantly for a superb economic bonus. As for gyms, they will also ascend economic status but eventually the fat person will lose their urge to eat, driven by the incessant requests of the nagging spouse.

A skinny fat person is a someone who appears visibly skinny with their clothes on. But, if you were to touch them or see them without clothing they are very flabby. This is very common in white people. Most white guys and girls have very little lean muscle tissue, which is why they are skinny fat people. Have you ever seen a thin white guy with no shirt on? Then you notice he has a soft pot belly and man boobs. This is a good example of what a skinny fat person is. With clothes on they appear thin to the eye, but if you were to see them unclothed their body is incredibly flabby and soft like jello. These body types are primarily due to genetics. Not everyone is naturally muscular nor will they become muscular and ripped. For some, it is not in their gentics to be muscular and well defined.

A person who doesn’t work out but maybe once a year, looks like they are in shape, but lacks great stamina, can’t even last on a treadmill for 10 minutes.

The innate ability to tell extremely funny and often self demeaning jokes that many fat people have.

when, for example, a fat person asks when the next stage of something will occur, when they could do it themselves. they're too lazy to do anything for themselves and huff/puff when someone else hasn't done it already

on december 5th you can slap any fat person you want no matter what they say

A girl who is of above average weight or below average looks has to develop a great personality to get guys. She is usually really cool to hang out with and/or really funny.