Dark Elesia is very fun to explore. Like with vanilla Elesia, I can only speculate about her character, but at least we get a glimpse of her personality and appearance from Kagetsu Tohya.
The first 4 pics are based on a design from Mashin Eiichirou's doujin (異人たちとの夏』)(https://twitter.com/eiitirou/status/1017392238110756864)

Putting her in any scenario instantly makes it so much fun!!
I love putting her with the other Roas, but my favorite would be with the Roa who calls Ciel his "daughter". It's fun to imagine Elesia teasing him because Roa bullied Ciel in her route ;w;

Recently, I've began to visualize her in a high school vampire trio with Warcueid and V.Sion, and with the help of my friends, more and more ideas poured in, and now my mind is just occupied by her speculative high school adventures.