ok this is random asf but i am extremely fucking sad so have this
i know that the reason why yuu doesn't mention their family is because they're a self-insert so naturally nothing abt their family or friends can be assumed but imagine if the reason why yuu doesn't mention them at all is because once they got teleported they forgot about them, they forgot a lot of things that were important to them, then one day for some random reason i am not mentally stable enough to come up with they get reminded of their family and friends, and they just break down crying. yuu had never cried in front of anyone from twst before, so they're all shocked, because yuu isn't simply tearin up or sum they're full of screaming and gasping for air they don't even have forced to stand up, they got hit will all the memories of their world, all of the good times they had, and also hit with the guilt of having forgotten about such an important thing
feel free to ignore this idk wtf this is
I've had this exact thought. Yuu just sad one days being like "I remember having a sibling that was a lot like you... but as time goes on I am forgetting their voice... their face"
Or imagine a Yuu that would talk a lot about their family. Yet as time goes on they go quiet. One day Deuce mentions it and they're like "siblings? What siblings?"