“In its principal and its fifths” — money that is repaid in the principal alone adds a fifth; money that is not repaid in the principal alone does not add a fifth.
In the sugya: When double or four/five-fold penalties already apply, the fifth of this verse is not added. The asham offering, however, is still brought.
Type of Learning
Miyut of chomesh vs multiple payments — fifth only when principal alone is repaid.
What Is Learned
Keifel or four-and-five replace the fifth, but the offering remains. The chomesh is not stacked on top of the multiple-payment penalties.