yoshiki*lisa (Risa Yoshiki) is an idol and actress. You might know her from Go-busters as Hiromu’s sister. Anyway, this song was the opening to some anime called “Gosick,” but I don’t know anything about it.
I translated the French in the translation because it’s actually important in this song and not a gimmick like in Wonderful Journey.
Some minor notes on the French:
saison – season, time
histoire – story, it can also mean “history,” but for this song I thought “story” fit better
mystification – mystification/mystery/etc. I just left it as is
maintenant – present, now
la clef a verite – “the key of truth” I don’t know if this is a regular phrase or not
reposer – rest/repose/calm/etc. I used gentle here because it seemed to work better