On [[danbooru_(site)|danbooru]], this tag is applied to both "[[Pillow]] fight" and "枕投げ ([i]Makura-nage[/i], [[pillow]]-throwing)"
The difference between the two is written in Wikipedia.

* "Wikipedia:Pillow fight":http://en.wikipedia.org/wiki/Pillow_fight
* "Wikipedia:Makura-Nage":http://en.wikipedia.org/wiki/Makura-Nage
枕投げ