What do vampires do at night?

Answer 1

Amost all vampires feed at night, to stay discreet. Most legends state that vampires cannot go in the sun, and each has a different reason. So, it is probably to hunt and avoid the sun.

Vampires are very much the person they were before they 'died'. So after they have done with necessities they engage in whatever activities they would normally have when they were alive.