Yeah. Fat and muscle aren’t mutually exclusive. While pop culture tends to think of losing weight as turning fat into ripped muscle, you can be both. Also, muscle weighs more than fat, so most people that try to lose weight by going into bodybuilding actually end up heavier than before.
In some circumstances, particularly the (historically) harsh winters of northern Europe and Asia, a thick layer of fat is provides insulation against the cold.
I’m told this can also benefit cold water divers, as the layer of fat can protect against the thermal shock from going into the water.
So, with some caveats, yes, it’s entirely possible to have someone that fits that description.