Kono Subarashii Sekai ni Shukufuku wo! God's Blessings on This Wonderful Choker!

Bundled with the 9th volume of the light novel. Kazuma finds a choker at Wiz's magic shop said to grant any one wish and decides to put it on. The problem? He'll die in four days from strangulation if the wish isn't granted. And Kazuma can't remember what he wished for, so he has no idea how his party members can help. The girls therefore have no choice but to submit to his every whim if they want to save him.