Edit: So, first we have Lily (Lilith), then Maha (Arabic: "Wild cow"), and now Sheth (Seth).
Looks like Gentsuki is picking Abrahamic names for the succubi. This makes a lot of thematic sense. Sheth in particular has a male (Hebrew) name, hinting at her ikemen ladykiller archetype.
Edit2: Aaaaand Lily, Maha was obviously giving you an opportunity for a date, but you're too tsundere to take it.
BTW that movie title reminds me of a certain KDrama featuring a kitsune gumiho.
There's something ironic about Sheth being the first lesbian succubus shown here as opposed to Lily, whose name in Japanese culture is usually a red flag for such a thing (in fiction).
ENTRANCE
perked up
My Girlfriend Is a Succubus.
I-It's not like I was waiting for you or anything!I-I'm not in any way remotely interested either! But it'll be rude if I don't put these to use!...Um...
Nothing major, really.She went to all that trouble after all. We can't let her kindness go to waste.
...Let's go then....Hmm, you have a point there.That aside, why exactly do you want to meet up in the Human Realm?A romance flick, is it...
Not that I'm particularly interested though...I was just wondering what to do with these two tickets I've received from SecChief Maha.And my bad for calling you over during a busy period.Nah, my shift starts in the evening, so I'm free up to then.Sorry for making you wait, Lily....Thought I came by early to pick you up. Looks like I should have came earlier though...
I can hardly wait! ...Maybe I might've arrived a bit too soon.