If you use Shadow Movement to sneak into houses and a pegasus team to pull the flying sleigh... yes, in this world, it's possible to become Santa Claus! But... the Christmas tradition doesn't even exist in this world. When Rimuru tries to explain it in detail to the people of Tempest, they end up summarizing it as a "party." The Christmas cake and presents are ready, and most importantly, Kaijin and the other Dwarves create gorgeous decorations that bring the Christmas mood to Tempest. On top of that, Eren and the children treat everyone in town with their heavenly singing.
Staying hidden is a cinch 
with Shadow Movement...
...البقاء متخفّياً سهلاً بحركة الظلّ
Wenn er sich versteckt, könnte er
das mit der Schattenbewegung machen.
Con Movimiento por las Sombras
puedes esconderte.
Con Movimiento por las Sombras
puedes esconderte.
Transport d’ombre
permet de se cacher facilement,
Con il Movimento ombra posso nascondermi facilmente
É fácil se esconder usando o
Movimento pelas Sombras...
Теневое перемещение
поможет остаться в тени…