There are a ton of tags containing "breast" without a breasts implication. These are the most popular ones:
between_breasts -> breasts
breast_biting -> breasts
breast_bondage -> breasts
breast_clinging -> breasts
breast_envy -> breasts
breast_feeding -> breasts
breast_hold -> breasts
breast_licking -> breasts
breast_lift -> breasts
breast_massage -> breasts
breast_pillow -> breasts
breast_poke -> breasts
breast_sucking -> breasts
breast_suppress -> breasts
breasts_apart -> breasts
breasts_outside -> breasts
hair_over_breasts -> breasts
mole_on_breast -> breasts
unaligned_breasts -> breasts
Obviously there's a few exceptions like breastplate, but almost every tag with "breast" in it should imply breasts.
Updated by jxh2154