When Bane has the damage steal buff from Enfeeble, an enemy Rubick can stack the damage reduction debuff on Bane.

Repro:
1. Skill the "Enfeeble Steals Damage" talent
2. Cast Enfeeble on an enemy
3. Have an enemy Rubick steal Enfeeble
4. Have them cast Enfeeble on you twice

Result: While you have the Enfeeble buff, the debuff stacks on you.

Expected: The debuff should never stack. This is the only scenario where the debuff stacks, and it shouldn't do that.