A fairly common trope in anime pictures involving a shorter character standing underneath a taller (and more endowed) character, with the head of the shorter pushing into the cleavage of the taller from beneath.
Also applies to any angle, so long as the breasts are being rested on the head of another character.
Often implies a significant degree of height difference.
This tag does not include the face-between-breasts position.
The following tags are aliased to this tag: headboob (learn more).
This tag implicates breast_rest (learn more).