Hi! First of all, thanks for the great work on this game! On second, thanks for sharing this concern! I think more devs should do this when they are in doubt of anything. The community always feel important to help!
It's hard to suggest what a good name could it be without sound a little bit cliche.
I will try to suggest somethings bellow to help you think on a final one:
-Line's Quest (generic)
-Line's Adventure (generic)
-Line of Fantasy
-Line's Lewd Experiment
-Lewd Journey
-Succex
-Succubus Journey
-A Fine Line
Idk, I have difficulties with that too. But I hope it helps you to find a final name!