The children of Dust Sans

A long time ago there was a king with a heart as cold as stone. Dust Sans wanted to bring endless genocide to the multiverse. On his 3rd attempt he gave the keepers of the 7 Core Souls an alternetive. Saying he would turn everything back to normal if he got a few things in return. Among his demands was the hand of a willing bride. Blueberry Sans, the soul of kindness, was the only one brave enough to accept his proposal and he was taken to Dust's castle. Then the impossible happend. They fell in love. After some time Blue was able to melt Dust's ice cold heart and reform him. After making amends to the rest of the multiverse, Blue and Dust got married and lived happily ever after.

That is... until a new element entered their lives.