C391 Why did he disappear?

Why is he gone?

Waiting for the few people to come out, then closing the door before leaving the restaurant. Unexpectedly, just as they were about to leave, a black shadow rushed into the restaurant from the side.

At this time, there was already no one left in the town. The few of them snuggled together, although from time to time there would be a few gusts of cold wind blowing in