i bet they sell these pics as bed sheet covers...

i bet too

Pillowcases.

blankets too

Yup and you guys are right. There was a pic somewhere in the internet that they owns pillow set for Eri and Yakumo

they certainly are dakimakura. If you want to see a tad larger versions of full body ones:
post #144406 post #144407 and post #144408
if they are not duplicates and get deleted XD but I did search a bit before posting