noctivagant (adj.)

"rambling or wandering in the night," 1620s, from Latin noct-, stem of nox "night" (see noct-) + vagantem (nominative vagans), present participle of vagari "to wander, stroll about, roam, be unsettled, spread abroad," from vagus "roving, wandering" (see vague). Related: Noctivagation; noctivagous.