Originating from a certain Call of Cthulhu tabletop roleplaying character sheet (prequel), this is the story of Crawley Carter, who takes a silver key and travels through various worlds to reclaim her past, all while interacting with cute, beautiful young women (?) No, wait, she's pursuing the truths among the stars and unraveling the mysteries surrounding herself! This is not a Stellaris fanfic! It isn't!
Crawley: Why do people keep confessing to me when I'm neither cheerful nor gentle?
Sylvie: I'm my big sister's devoted simp.
Saeko: She's pretty.
Miyamoto: She's pretty.
Marian Bell: Lolis are the best.
Crawley: ?????
Main plot: In pursuit of the truths among the stars, Crawley Carter, descendant of Randolph Carter, sets out on the road to truth with a silver key in hand and a band of followers at her side, journeying together with Sylvie Carter.
Side plot: Laura Stuart's coming-of-age journey, and her adventures wreaking havoc on the world alongside Aurelia.
World progression: Twisted Mythos (prequel) - Kengan Ashura - Highschool of the Dead - SAO - The Lost Seven Years (interlude) - Xuanyuan Qixia Zhuan: Mark of Heaven (crossover) - Moriarty the Patriot (Laura side story) - That Time I Got Reincarnated as a Slime - Tsuki ni Yorisou Otome no Sahou - Dark Souls 1 - Epic Seven - Harry Potter