Rimuru is building a dungeon in preparation for the upcoming festival. It will feature treasure chests containing weapons made by Kurobe, and Veldora will inhabit the deepest floor as the final boss. Then Milim suddenly shows up with a suggestion...
I can finally move past 
spending my life all alone!
!لم أعُد أقضي حياتي وحيدة أخيراً
Damit bin ich endlich nicht mehr allein!
¡Por fin dejaré de estar sola!
¡Por fin dejaré de estar sola!
Ça y est,
je ne suis plus toute seule !
Ora non sono più sola!
Finalmente não preciso mais
levar a vida sozinha!
Больше я никогда не буду одна-а-а-а-а-а-а!