Seemingly normal humans with a dark truth.Your Constitution score increases by +2, 

Hunger. You can only receive nourishment from human flesh. When consuming other food, you must succeed a DC 15 Charisma saving throw or Performance check, your choice. On a failure, you vomit. Regardless of whether or not you vomit, it will not fulfill your food requirement for the day.

Extreme Recovery. Ghouls may regrow limbs or other parts of the body during a long rest. If you regenerate a limb during a long rest, you do not replenish Hit points, Hit dice, or spell slots. Along with this you add your proficiency bonus to your hit dice when you use them to heal.

Extreme Feeding. Ghouls are very dependent on their diet and must consume flesh (see Hunger) to fulfill their food requirement, after which they are satiated for 2d20+your Constitution modifier days. If they eat before they require food again, it does not stack and they must roll again. 3 days before they require food, they must succeed a DC 12+1 each day they do not eat Constitution saving throw at the end of combat. If they fail the save, they suffer one of the effects in the short term madness table located in the DMG for 1d10+15 minutes. While under these effect, they do not gain the benefits of Extreme Recovery.

Languages. Common, and 1 other language. Ghouls will usually learn a language from their local area or hometown to better blend in.

Ghouls are unable to be surprised unless something dulls their senses (hard rain)

your Strength or Dexterity score increase by +1.