nipple penetration
When an object, finger, penis, tentacles or object is inserted inside one's nipples, thus the nipple being penetrated.
Tag with nipple object insertion if it's an inanimate object. If it's an injection use nipple injection instead.
If it's the nipple penetrating something else tag with reverse nipple penetration instead.
See also
The following tags are aliased to this tag: nipple_fuck (learn more).
The following tags implicate this tag: nipple_object_insertion (learn more).
