This is a character from a free-to-read web-novel ( http://novel18.syosetu.com/n3271bm/ ) called "Only I Am Not Attacked In A World Overflowing With Zombies". It's apparently getting a visual-novel, as indicated by this trailer ( https://www.youtube.com/watch?v=dC671TggL0A ), around 0:38~0:40 you'll see the scene.