I've been honestly thinking about this stuff for MONTHS ever since I first finished playing the demo and I've come up with countless theories about Alexis and what the hell that guard (or well, the one who's controlling him) meant by that comment about a Rosenkreuz of all people putting chains on somebody. That combined with that scene at the beginning of the game when Serin looks at the markings and talks about it being a blessing that the Rosenkreuz can control all the elements through that and Alexis saying "It's not entirely a blessing" makes me think that yeah .. it's some type of curse. Because I've also been asking myself why the hell the Rosenkreuz family has the power to control all the elements in the first place, like where did they get that power from? So I've been thinking .. maybe it's some type of "deal with the devil" situation where they gained that ability through a ritual or something but there's of course a price to pay and that has to do with the pain Alexis often seems to be in when they cast magic .. maybe the magic feeds off their energy or life force or .. something, idk.
I am definitely looking forward to find out (and to get answers to a lot of others questions I have from playing the demo) in a few days when the full game is released!!AAAAAAH, I just know it's gonna be amazing :D