I just finished reading/rereading some good books and reaped some excellent new words to play with. They've been jangling about in my head all week.

INSOUCIANT:
Marked by blithe unconcern; nonchalant.
[French : in-, not (from Old French. See in-1) + souciant, present participle of soucier, to trouble (from Old French, from Vulgar Latin *sollictre, alteration of Latin sollicitre, to vex. See solicit).]

LUGUBRIOUS:
Mournful, dismal, or gloomy, especially to an exaggerated or ludicrous degree.
[From Latin lgubris, from lgre, to mourn.]

CREPUSCULAR:
1 : of, relating to, or resembling twilight
2 : active in the twilight

Sigh... I love writers who can use humongous words without impairing the juicy flow of their writing.