de-particle-kimetsu-no-yaiba.png

Translation

• Context: an oni 鬼 counts the number of people in a group.
• juu ni... juu san
  十二･･･十三
  Twelve... thirteen.
• de で
  And given that. (this is the conjunction.)
• omae de juu yon da
  お前で十四だ
  With you, [it] is fourteen. (this is the numeric limitation function.)