Master of a Thousand Cuts (5e Feat)

Prerequisites: Proficiency with a Finesse weapon
You have honed your skills with weapons of finesse and are able to leave painful slices

While Dual-Wielding Finesse weapons you may add your ability modifier to the damage roll of the off-hand weapon.
Targets struck by your two of these attacks consecutively bleed as long as it is done with your finesse weapon. At the beginning of their turns, they take 1 necrotic damage from their injuries, this effect stacks, increasing the necrotic damage taken per turn by 1 on each additional time the previous condition is met, to a maximum equal to your proficiency bonus.
The necrotic damage taken from bleeding stops when the target receives healing, or when a Medicine check to close their wounds succeeds against DC. Your DC for this is 8 + your proficiency bonus + your Dexterity modifier.