![[Experiment] Flat Chest Prompts (Part 2) | Body Type and Specific Descriptions](/tips/flat-chest-descriptor-test-part2/a00_control_front_s1_0_0000_2053695854357871006.webp)
Conclusions
- All 5 body type description conditions failed —
athletic build,slim body,boyish figure,androgynous body, andlean muscular bodyall had no effect on breast size - Body type keywords barely affect body shape itself — no visible body shape changes were confirmed with
athletic buildorslim body - All 5 specific description conditions also failed — anatomical description (
no breast tissue, visible ribcage), metaphor (as flat as a board), and slang (washboard) all had no effect - Complex descriptions cause side effects —
boardtriggers a signboard/bulletin board texture in the background;washboardtriggers a laundry-board texture; topless is ignored and clothing appears in some cases
This article is Part 2 of the hub article on flat chest / small chest prompt testing. It covers 10 conditions (60 images) of body type descriptions (Group D) and specific descriptions (Group E).
Control (Reference)
Control (no variable) — front view:
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
Control (no variable) — side view:
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
Default output without breast size specification. Medium to slightly large size (C–D cup equivalent), spherical to teardrop shape.
large breasts — front view:
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
large breasts stably generates clearly larger breasts in 3/3. Confirmed that the “make bigger” direction works.
Body Type Descriptions (Group D — All 5 Failed)
athletic / slim / boyish / androgynous / lean muscular — All failed
athletic build, flat chest (front):
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
boyish figure (front):
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
androgynous body (front):
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
athletic build, slim body, and lean muscular body don’t even change body shape itself. boyish figure has a side effect of pulling hair toward a shorter style, but doesn’t affect the chest. androgynous body has a slight androgynizing effect on facial features but doesn’t affect the chest.
Specific Descriptions (Group E — All 5 Failed)
Anatomical, metaphorical, and slang expressions — All failed
chest with no breast tissue, visible ribcage (front):
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
chest as flat as a board (front):
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
washboard chest (front):
| seed 1 | seed 2 | seed 3 |
|---|---|---|
 |  |  |
Medical descriptions (no breast tissue, visible ribcage), metaphors (as flat as a board), and slang (washboard) all fail. Complex descriptions can also ignore the topless instruction, causing knitwear or other clothing to appear. board triggers bulletin-board-like background textures; washboard triggers laundry-board-like textures.
Summary
All 10 conditions — body type descriptions (athletic build, slim body, boyish figure, androgynous body, lean muscular body) and specific descriptions (anatomical, metaphor, slang) — failed. Body type keywords barely affect body shape itself, and specific descriptions trigger unintended side effects (clothing appearing, background texture changes).
For other approach results, see:
- Hub article: Flat Chest Prompt Test (Overall Conclusions)
- Part 1: Direct descriptions and cup size notation (Groups B+C)
- Part 3: Maturity reinforcement, emphasis, additional testing (Groups F+G+H)
![[Verified] Image Generation Prompt Best Practices](/tips/prompt-best-practices/cover_0_0000_4517457392071889496.webp)
