Generation Iii
Liquid Ooze
Draining causes injury.
Detailed Effect
Whenever a Pokémon would heal after hitting this Pokémon with a leeching move like Absorb, it instead loses as many HP as it would usually gain. Dream Eater is unaffected.
Pokémon With Liquid Ooze
4 canonical Pokémon forms can have this Ability.

Tentacool 
Tentacruel
Gulpin
Swalot