I have figured it out! Daithi's song will be 'Shells' by Laurel A soft song full of pain and loss, and pretty much sums up his backstory. He loses someone close to him, and fights a long, hard battle to get her back Richards song 'Antigravity' is about the world being full of shit and the signer taking comfort in the stars. The song 'Dark on me' by Starset also describes Richards backstory well. Matryoshka is Czarna's song. It isn't really about anything, no events are described but the song feels like a descent into madness, nonsensical and hints at some kind of lost memories. As for Czarna's backstory, you will have to try and work that out for yourself.