An obese Man or Woman who makes no attempt to get in shape or improve their diet. A My-one often revels in their physical condition; and drinks and eats excessively without regard for their own health.
Oh dear - Look at her, such a My-one. She should really order less hamburgers.
Monty:I cant belive I went home with that My-one last night
Tom: how did you both fit in the cab?