Lacking both High Fat Index and Muscular Index, these tropes are about people having a narrow physique. Can overlap with Skeletal Tropes.
- Adaptational Slimness: The adaptation slims down a chubby, bulky or busty character from their source material.
- Baby Don't Got Back: A person with a flat ass.
- Big, Thin, Short Trio: A group consisting of a person who is tall and thin, a person who is big and obese and a person who is short.
- Chubby Mama, Skinny Papa: The father is skinny and the mother is fat.
- Fat and Skinny: A pairing consisting of a skinny person and an obese person.
- Geek Physiques
- Intentional Weight Gain: A skinny person wants to gain weight.
- Lean and Mean: A skinny person who is evil or just a jerk.
- Muscle Angst (male version)
- Noodle People
- Nothing but Skin and Bones: Where the physique clearly becomes unhealthy.
- Weight Woe