It looks like a mobile/browser game that is having a colaboration with Tsuki ga michibiku series. But it also look like an original Tsuki mobile games.Other than Mio and Tomoe, i don't recognize the rest of the character.
Here's the game in question
http://www.4gamer.net/games/366/G036697/20161222148/
Found it while i was looking for vol 11 & 12 ln cover