Deltarune really is a story all about the web, huh?
(If you don't know about the magnus archives, don't worry, I don't either. But the web is about the fear of manipulation, of control and all the different ways that someone can have their freedom stolen from them)
And Deltarune goes and hits almost every facet of that fear that it can.
Most obviously, It's about posession and physical control, but it's also about manipulation and family loyalty and being held to age old promises, how your past and the guilt from it affects you
It's about being a kid (or anyone else) with no power of your own, beholden to people far more "important" than you and the fear of what will happen when you're no longer wanted or needed by them
It's about the roles people are stuffed into,
about the parts people hide from others and how others expectations affect you or how you can't choose what you were born into
(Susie is held down by her reputation as a "bad kid" and a deliquent and has always been told there is things she can't do. Berdly is tethered to people's high expectations of him and is constantly putting on an act he can't maintain. Ralsei worries it would be selfish to have normal teenage needs, desires or emotions because he's not "supposed to be" real.)
Sometimes it's just about feeling inadequate and never chasing what you want, even if there's nothing physically stopping you from doing so
It's quite literally about fate and destiny, the prophecy that binds all of the heroes, that dooms them to some horrible fate we don't know about but holds them all down and dictates how they act
(Not only that but the events of the story are foretold exactly by the prophecy down to every minute detail. Talk about determinism!)
It's about love and LOVE. It's about designated love interests who don't actually want to be together and the horror of fated romance and a wedding ring that just makes everyone miserable
It's also about You. You are given enormous power over the main character, probably with the help of the people holding control over them in their hometown and you get to decide what to do with it. You could try to mitigate the damage the possession causes and maybe even try to help this kid or you could just⦠Make everything worse. For no other reason than you simply can. Just because you have power over these children.
....Maybe that's what so special about it, it's not just about posession or manipulation or survivor's guilt, it's not just about hierarchy or social roles or expectations, it's not just about fate and the way things are "supposed to be", it's not just about abusive romance and it's not just about having power over others. It's about all of this, and that slowly forms a picture.
So yeah... A game about all the strings that hold you down or force you to dance against your will, be they personal, societal or indeed magical... In other words a game all about The Web!