The user can absorb life-force/energy, vitality and health, while removing it from the source, into their body and use it in various ways, gaining some form of advantage, either by enhancing themselves, gaining the drained power, using it as power source etc., either temporarily or permanently.
As many superpowers are derived from life force, user may be able to absorb them from the targets. Any attacks derived from superpowers are also vulnerable to such abilities, as the energy and matter produced contains the user's life force, which can be drained and rendering the attack useless. Extended drain may result in extended or permanent effects, or even death.
Cliford DeVoe/The Thinker (The Flash 2014); via his chair
Linda Tavara (Heroes)
Nora Darhk (Legends of Tomorrow)
Bo Dennis (Lost Girl)
The Annihilator (Mighty Med)
Hapax the Elder (Mighty Med)
Gnatu (Power Rangers Mystic Force)
Chrissy Parker (Smallville)
Andie Bates (The Gates)
The Ghostmaker (Torchwood)
Gardiner Brothers (Witches of East End)
Money Dopant(Kamen Rider W)
Goth (His Story/ReaperTale)
Ruri'iro Kujaku (Bleach)
Eyes of Hades (Doctor Who)
Vladimir's Offering (DoTA 2)
Dragon-Scaled Tessaiga (InuYasha)
Ghost ÄRMs (Marchen Awakens Romance)
Soul Gem (Marvel Comics)
Amethyst Shield (Saint Seiya)
Blue Rose Sword (Sword Art Online)
Black Ops Psionic Amplifier/Psi Amp (System Shock 2)
Mad Mod's jeweled cane (Teen Titans)
Reiki (Tenjho Tenge)
Bracelet of Anubis (The Mummy Returns)
Yumichika's (Bleach) Ruri'iro Kujaku can create energy vines that drain the life force of enemies.
Yhwach (Bleach) using Auswählen to take the powers, and life-force, of other Quincy to empower himself, or to revive his fallen Sternritter elites.
Rei Ōgami (Code:Breaker) losing control over Beelzebub, who starts to devour life force of everyone around it, even Rei's.
Sakura Sakurakōji (Code:Breaker) using her Rare Kind's Death God powers, draining vitality, and prolonged exposure would lead to death.
Sakurako Sakurakōji (Code:Breaker) using her Life Force which she can either give via a kiss or drain via a bite.
Zed (Code:Breaker) using his ability Death to induce death by draining life from his victims, which even Rare Kinds cannot resist.
Freezing Hōkabe (Code:Breaker) using his Ice to freeze a group of power users, and drain them of their life force to enrich his own reservoir of vitality to near infinite amounts.
The Millennium Earl (D.Gray-Man) devours the "helix of life", or one's soul, from Danny, causing him to disintegrate.
Yin/Izanami (Darker than Black) after awakening displayed the ability to kill contractors or humans by merely drawing a blue essence from them, which is their lifeforce or soul killing them instantly.
Android 19 (Dragon Ball) using the pads on his palm to absorb life energy, whether it be incoming ki attacks...
...or by physical contact.
Cell (Dragon Ball Z) uses his tail to absorb life energy, whether by stabbing his victims or swallowing them whole.
Super 17 (Dragon Ball GT) has an energy absorption barrier installed in him, absorbing life energy attacks to increase his own strength, even the 10x Kamehameha.
Tōshū (InuYasha) wielding the Dakki, a sword crafted from a dragon-demon's scale, which can drain demonic life energy. Unfortunately, Tōshū's human body couldn't handle the demonic energy, leading to his death.
Inuyasha (InuYasha) wielding the Dragon-Scaled Tessaiga, which allows him to drain demonic life energy. However, being half-demon causes him to be burned by the energy before he absorbs Nikosen's Seimeikan.
Nikosen (InuYasha) is a former hermit who absorbs life force from trees to extend his life. So long as his Seimeikan is undamaged, he can regenerate, though this costs him large amounts of energy that he must replenish via eating.
Kisame Hoshigaki (Naruto) wielding the Samehada, a sentient and ever voracious sword that can detect and eat chakra via cutting through it....
...it can even share chakra with its wielder to replenish their chakra supply and regenerate wounds...
...and his Water Style: Super Shark Bomb Jutsu/Water Release: Great Shark Bullet Technique, which would absorb chakra from the opposing technique to increase its own strength, making the impact even more devastating.
Nagato/Pain (Naruto) using the Blocking Technique Absorption Seal to absorb chakra from a technique via the Gakido/Preta Path, and can even absorb from the enemy by holding them down…
...rendering chakra based attacks useless against him.
A powerful guardian entity for the user, the Susanoo (Naruto)...
...can also at the same time drain the user of their life force and vitality if not stabilized, which was one factor leading to Itachi's death.
Madara Uchiha (Naruto) using Wood Release: Wood Dragon to drain the victims of their chakra, enough to even capture a Tailed Beast as big as Kurama.
Fūka (Naruto) draining Naruto's chakra using her Execution by Kiss technique, which allows her to gain his life force and elemental chakra affinity, as well as enforcing her own.
The Black Fog (Pokémon) trapping its foes in a dream and then devouring their souls.
Gengar (Pokémon) using Dream Eater on Blue, trapping him in a dream and devouring his life energy.
When Reiki (Tenjho Tenge) is in the hands of a special power user, it consumes a vast quantities of ki, driving the user insane and disabling special powers of those around it.
Metarex (Sonic X)
Aside from accelerating plant growth, the energy waves emitted by Final Mova (Sonic X) drain the life force from all animal life forms.
Charlotte Linlin/Big Mom (One Piece) using her Soru Soru no Mi powers to extract one’s soul, and effectively lifespan. She won't even hesitate to use this on her own children, stripping a lethal 40 years worth out of her son Moscato.
Sarah Band’s (Marchen Awakens Romance) Ghost ÄRM, Ark Torff gives her the power to drain people’s life energy.
The terrible truth of Ghost ÄRMs (Marchen Awakens Romance) is that they gradually eat away at the user’s life force.
Kurumi Tokisaki (Date A Live) can use the City of Devouring Time to absorb other people's life force to increase her own.