>entire Susie story ars is that her childhood sucks and she want to be part of Dreemurr family
>her story with piano also ties to Kris
>all her bonding and interaction also to Kris
I'm like 99% sure the narration is trying to make Krusie happen so she would marry into Dreemurr family through Kris but there is that 1% of possibility Toby want to sibling zone Kris and make Toriel adopt Susie.