Basic Trope: An Always Female duo composed by a slender girl and a busty girl.
- Straight: Alison has A-cup and is seen together with Diana, who has D-cup.
- Exaggerated: Alison doesn't have any breasts and even has holes in her chest, while Diana has breast hypertrophy, and they are an unseparated married couple.
- Downplayed: Bella has B-cup and is seen together with Claire, who has C-cup.
- Justified:
- It Runs in the Family, Alison's mother has small breasts while Diana's mother has large breasts.
- Alison and Diana find each other's body type attractive, which is why they are together in the first place.
- Alison hasn't had that growth spurt yet, unlike her older sister Diana.
- Inverted: All female characters in the show has the same cup size.
- Gender-Inverted: Alex has Teeny Weenie and is seen together with David, who has Gag Penis.
- Subverted:
- Diana is thought to have big breasts, but it's revealed later that she wears pads or Fake Boobs.
- It turns out that "Alison" is actually a Dude Looks Like a Lady.
- Turns out Allison is actually quite young... and once she's grown up, her bust size is the same as Diana.
- Double Subverted:
- But Alison also looks small just because of her chest binder or compression bra.
- Diana still has larger breasts than Alison even when she doesn't wear pads.
- Alison was lying about being a guy.
- Parodied:
- Alpha Bitch-wannabe Girly Girl doesn't have any breasts, while the Testosterone Poisoning Tomboy is very busty, even being transgender and Driven to Suicide due to it.
- Alison holds a sign that says "I need a female friend, but she'd better be busty so I can say some A-Cup Angst phases."
- Zig-Zagged: Sometimes Alison is seen with Diana, sometimes is seen with Amy, who also has small breasts like her.
- Averted:
- Alison and Diana have the same cup size.
- None of the female characters in the story interact so their breast sizes can't be contrasted.
- Enforced:
- Either Buxom Beauty Standard or Madonna-Whore Complex.
- It's a lingerie advertise, and the producer wants to show how their bras look like when apply to different bust sizes.
- Lampshaded: "Alison and Diana look so different because of their breasts!"
- Invoked:
- Big-Breast Pride Diana seeks a girl with smaller breasts to make her feel better about herself (or vice versa).
- Alison is attracted to a busty girl because Buxom Beauty Standard, so she asks Diana to date her.
- Exploited: ???
- Defied:
- Alison and Diana refuse to hang out together.
- Either Alison get breast implants or Diana gets a breast reduction, so their breast size is equal.
- Discussed: ???
- Conversed: ???
- Implied: Someone spots bras with two obviously different cup sizes hanging on a drying rack.
- Deconstructed: The distinctive breast size makes Alison and/or Diana feel insecure about their body.
- Reconstructed: Alison and Diana find moderate happiness since they stop comparing each other.
- Played For Laughs: Arrogant Petite Pride Alison who dislike feminine appearances and Big-Breast Pride Alpha Bitch Diana is always seen Cat Fighted, and Alison usually loses the fight because Diana uses her breasts to slap Alison's face.
- Played For Drama: Both A-Cup Angst and D-Cup Distress are applied since they are envied each other.
- Unparodied: The story is Trans Tribulations starring Alison (formerly known as Allen) doesn't have any breasts because she doesn't even begin her transition or only transition very recently, and Dillan (formerly known as Diana), who is dysphoric of his breasts and want to get rid of these ones. They hang out together because they are the only Transgender people in this transphobic town.
Looks at that Bust-Contrast Duo! they have totally different bra sizes.
