The is a paid DLC for the PC version of Gal Gun 2*. Unlike the standalone Gal Gun VR* (which was more of a tech demo), this DLC allows you to play the entire main game in virtual reality.
The for Gal Gun 2* was officially released as a downloadable content (DLC) expansion on November 28, 2018 . Unlike the standalone Gal Gun VR* title, this mode is an add-on that allows you to experience the entire Gal Gun 2* campaign, including all shooting stages and the signature "Doki Doki" sessions, in virtual reality . How to Get the VR Mode Gal-Gun 2 - Doki Doki VR Mode download 2019
Once installed, right-click Gal Gun 2* in Steam, go to Properties, and add -vr to your launch options. The is a paid DLC for the PC version of Gal Gun 2*