Damnit, why does harusaki_iwai have to make such adorable pictures. BTW, what the fuck does an actual night sparrow look like? That's been driving me crazy ever since I was first introduced to Mystia.
There might not be an actual night sparrow. That, or it's known under a different name here in the west. Either way, all the search hits I get for nigght sparrow are touhou related. There are some nocturnal birds which could be a candidate, however.