It is only available through DL.site for the time being, but the game will release this winter for PC via Steam and on PlayStation 4 as a PlayStation VR title.
The PC version of the game comes in a Rem version and Emilia version, and is compatible with Oculus Rift and HTC VIVE devices.
Publisher Gugenka released a VR interaction smartphone game for Re:Zero that lets you rest on Rem’s lap or get fed by Emilia, and it is now available in Japan for PC through DL.site for 2,160 yen.